Endarire
2015-06-24, 03:57 AM
Intro
Greetings, all!
I've pondered long and hard about 3.5's psionics. Which powers are the most powerful for a Psion? (That is, their effect is powerful and versatile on its own, but can also combine with other abilities and items for synergy.)
Assumptions
The following list of powers assumes the character has access to all of 3.5's material. I assume the a character has each power's 'accessories' - items, feats, races, etc. - that directly improve that power. These powers assume a Psion with a manifester level at least equal to his HD.
I also assume Complete Psionic's nerfs are not in place. Astral construct was probably hit the hardest by Complete Psionic wherein a manifester is limited to one Astral Construct at a time. Other casters, like Druids and Clerics and Wizards, have no such limit on the number of active summons.
Criteria for Judging
A power must be on the general Psion list or any Psion discipline list. I generally give preference to lower-level abilities since they're more likely to see play, and these powers have more metapsionic options available. It's easier to use Extend Power and Quicken Power on astral construct than fusion.
Beyond that, I consider what a power does on its own, what it couples with (like Metamorphic Transfer for metamorphosis), and how easily a character/player can use this ability to its fullest. How frequently is this ability useful, and how useful is it? How simple is this ability to understand?
Why make this list?
Because I was pondering this before bed and wanted to write it down for the world to enjoy! I also wanted to hear the opinions of others.
Runners Up
Runner Up Alpha: Forced Dream (Magic of Eberron).
Manifest forced dream, then while the power's duration hasn't yet expired, the subject may spend a swift action to undo all the actions that happened since the start of its turn. (PP spent to manifest forced dream are not restored, and spending a swift action to restart the turn ends the power.)
Forced dream is basically a one-time do-over - especially useful in situations where you know something dangerous is ahead, but don't know just what. Did the antagonist just shrug off your energy missile? Did a trap leave your party trapper hurtin'? Did you say the wrong thing in a social situation? Was someone hit by an attack of opportunity? Did the subject fail a crucial roll, like an accuracy roll or a skill check? Try again!
Runner Up Beta: Energy Missile (http://www.d20srd.org/srd/psionic/powers/energyMissile.htm).
Energy missile is a level 2 Kineticist, Medium range power that can hit up to 5 separate targets, each up to 15' apart. When you absolutely want to blast, this is the go-to power. And any full manifester can learn this power via Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge[/url) as soon as level 5!
It's the lowest-level multi-target power that doesn't require augmenting to affect more than 1 target. It also targets Fortitude (cold damage) or Reflex (fire, electricity, or sonic). You can deal more damage directly with cold or fire, increase your DC with electricity, or hurt pretty much anything with sonic. Sure, it's power point inefficient compared to buckets of Black Lotus poison (see below), but it's probably the best targeted damage power there is.
I prefer to ignore the Complete Psionic nerfs to this power. (This power becomes notably weaker with them.) Ask your GM what he thinks.
Runner Up Gamma: Temporal Acceleration (http://www.d20srd.org/srd/psionic/powers/temporalAcceleration.htm).
As a swift action, gain another turn. It's a psionic, 1-round (but augmentable for more!) version of time stop (http://www.d20srd.org/srd/spells/timeStop.htm) available at character level 11.
This is quite powerful, but hampered by 2 main drawbacks. First, anticipatory strike (Complete Psionic) exists and does a similar (nae, better) thing as a level 5 power instead of a level 6 power. Second, temporal acceleration renders the target Shaken at the end of it. Find a way to become immune to Shaken (like from being Undead or otherwise immune to fear) and you can spam this power!
Runner Up Delta: Fusion (http://www.d20srd.org/srd/psionic/powers/fusion.htm)/Mind Switch (http://www.d20srd.org/srd/psionic/powers/mindSwitch.htm) (Tie).
Fusion lets you combine yourself with another willing creature of your size category or smaller. Then manifest this power and do it again. And again. And again. Nothing in the power's description prevents you from doing this. Just be mindful of the 50 XP cost each time - a proverbial drop in the bucket at level 15+.
Fusion works best when combined with astral seed (http://www.d20srd.org/srd/psionic/powers/astralSeed.htm) and form-altering abilities like metamorphosis (http://www.d20srd.org/srd/psionic/powers/metamorphosis.htm) to give yourself a more permanent version of what you turned or/and fused into. (You need to manifest astral seed, die within 30 days, then wait 10 more days to grow a new body. You also lose a level.)
Meanwhile, mind switch lets you - also for an XP cost per manifestation - switch minds (and therefore bodies) with another subject within range. It's a lower-level solution (mind switch is a level 6 Telepath power opposed to fusion which is a level 8 Egoist power) and one native to Telepaths, but produces a similar effect: You have a spiffy new body. Yes, astral seed still also works. Yes, you can use this to take control of diplomats and authority figures and cause chaos.
Runner Up Epsilon: Psionic Minor Creation (http://www.d20srd.org/srd/psionic/powers/minorCreationPsionic.htm).
Psionic minor creation is a power that any character (even your Psicrystal!) can learn at level 1 via the feat Hidden Talent (Expanded Psionics Handbook), assuming the character has at least 11 CHA. Any manifester capable of manifesting level 2+ powers can spend a feat upon Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge[/url) and learn this power as soon as level 3 - assuming they don't know it already!
Manifesting this power probably requires a Craft skill check to make anything complicated enough to warrant a Craft check. (GMs, I recommend using this rule.) Still, being able to make buckets of Black Lotus plants (which you can turn into poison later if it isn't in poison form already) is still spiffy. You can also make less lethal items like ropes and ladders, but c'mon. Did you really learn this power for reasons besides making buckets of poisons?
Combine with Linked Power (Complete Psionic) to reduce the 10 minute manifesting time to 1 round.
Runner Up Zeta: Psychoport ('Psionic Teleport') (http://www.d20srd.org/srd/psionic/powers/teleportPsionic.htm).
Simple. Straightforward. Move from place A to place B (preferably with your party) as a standard action. No somatic nor verbal component. This level 5 Nomad power (also obtainable with (Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge)) lacks the guaranteed accuracy of the generally-available level 8 psionic greater teleport, but is available as soon as level 9 for Nomads!
Use this power to warp 100 miles per manifester level per manifestation. It's the ultimate mid-level get-in or getaway power!
Finally, teleport and psychoport are some of my favorite abilities. Plane shift is up there too. (Yes, I'm biased. I like to explore rapidly and laugh as others can't touch me. Ha-ha-ha-ha-ha-ha.)
The Winners
#5: Psychic Reformation (http://www.d20srd.org/srd/psionic/powers/psychicReformation.htm).
In short, you can change the feats, skill ranks, and powers known of yourself or a willing ally - with a 10 minute manifest time* and 50 XP spent per HD of change. (That's a maximum of 1000 XP for a level 20 character. No biggie!)
Psychic reformation is on this list due to its potential power. Want to be a blaster instead of a mind controller today? PsyRef! Want to make an ally suddenly an expert in this weapon type he just found? PsyRef! Want to learn some item creation or metapsionic/metamagic feats then swap 'em out when done? PsyRef!
*Add Linked Power (Complete Psionic) on PsyRef linked to a power with a shorter manifest time - like, oh, catfall (http://www.d20srd.org/srd/psionic/powers/catfall.htm) - and suddenly you're swapping builds as a standard action (or, with catfall, an immediate action) with 1 round of delay!
#4: Anticipatory Strike (Complete Psionic).
It's a level 5 Psion power that lets you, as an immediate action, take another turn. You may only use this power once per round, and it uses your swift action from your next turn, but oh golly! What can you do with an extra round of actions? Perhaps manifest a power from this list!
Anticipatory strike is the power from this list that has the least extra support. It doesn't need it.
#3: Synchronicity (Complete Psionic).
Synchronicity is a level 1 Psion power from Complete Psionic that lets you "ready a standard action (without spending an action to do so) and use it whenever you choose before your next turn." It has a 2PP augment which lets you ignore the 'you must declare what action you are readying' clause and just take a standard action.
On its own, synchronicity is OK - perhaps even balanced. Let's not consider this in a vacuum. You can use Linked Power (Complete Psionic) to give yourself extra standard actions. Yes, that's as powerful as it sounds. Want to make it even more delicious? Couple Linked Power with Metapower (Complete Psionic) to reduce the PP cost by 2.
-Manifest sense danger (Magic of Eberron) coupled with synchronicity to, for 10 minutes per manifester level, get an extra standard action at the start of each combat.
-Manifest schism (http://www.d20srd.org/srd/psionic/powers/schism.htm) and make your second mind manifest synchronicity every turn, then use the action from synchronicity to manifest another power at full manifester level. (Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge) can get you schism at character level 9, but you'll probably want to hold off on that until level 12.)
-Apply Twin Power (http://www.d20srd.org/srd/psionic/psionicFeats.htm#twinPower) or/and Quicken Power (http://www.d20srd.org/srd/psionic/psionicFeats.htm#quickenPower) to synchronicity. Applying both requires 2 psionic focuses, like from Psicrystal Containment (http://www.d20srd.org/srd/psionic/psionicFeats.htm#psicrystalContainment). (AmberVael mentions the difficulty of actually using two readied actions here (http://www.giantitp.com/forums/showsinglepost.php?p=19446047&postcount=18). Ask your GM.)
-Manifest psionic contingency (http://www.d20srd.org/srd/psionic/powers/contingencyPsionic.htm) with a fully-augmented synchronicity, possibly with Twin Power (http://www.d20srd.org/srd/psionic/psionicFeats.htm#twinPower) attached, with the triggering condition being 'when I want this to trigger.' Augment synchronicity as desired.
The main reason synchronicity isn't ranked higher on this list is because, on its own, synchronicity costs PP for potential. You could sniff your finger as a standard action (usually a waste), or make a single attack, or manifest a power, or cast a spell, or... The true power of synchronicity also requires you couple it with something else, especially Linked Power. Without these or similar ways to get extra standard actions, synchronicity is forgettable.
#2: Metamorphosis (http://www.d20srd.org/srd/psionic/powers/metamorphosis.htm)/Greater Metamorphosis (http://www.d20srd.org/srd/psionic/powers/metamorphosisGreater.htm) (Tie).
The Polymorph Handbook (http://www.minmaxboards.com/index.php?topic=519.0) forms a good basis for why this series of powers is in the #2 spot. Unlike the polymorph series of spells, metamorphosis is self-only, allows you to turn into objects, and the Overchannel (http://www.d20srd.org/srd/psionic/psionicFeats.htm#Overchannel) feat (and other means of boosting your manifester level) lets you assume forms of a higher HD total than your HD. And any Psion, Wilder, Erudite, or full manifester can take Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge) at character level 9 to learn metamorphosis. That's rad!
Wanna know what else is rad? Metamorphic. Transfer. (http://www.d20srd.org/srd/psionic/psionicFeats.htm#metamorphicTransfer) Requires 13 WIS (which you're gonna have anyway if you're going the Thrallherd route due to the Inquisitor (http://www.d20srd.org/srd/psionic/psionicFeats.htm#inquisitor) feat prereq) and manifester level 5. In exchange, you can use 3 supernatural abilities per day from any form you assume. Oh look! A Choker (http://www.d20srd.org/srd/monsters/choker.htm)! Oh look! A Hydra (http://www.d20srd.org/srd/monsters/hydra.htm)!
Greater metamorphosis is basically a better version of metamorphosis + Metamorphic Transfer in the form of a single power. It's also a level 9 power - putting it near the end of the expected campaign and into the 'very nice if you get there, but largely theoretical' territory.
#1: Astral Construct (http://www.d20srd.org/srd/psionic/powers/astralConstruct.htm).
This was a close call with the metamorphosis line of powers, but no other power provides such tremendous versatility and combat ability - from level 1! It's also a power that any character (even your Psicrystal!) can learn at level 1 via the feat Hidden Talent (Expanded Psionics Handbook), assuming the character has at least 11 CHA. Any manifester capable of manifesting level 2+ powers can spend a feat upon Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge[/url) and learn this power as soon as level 3 - assuming they don't know it already!
Each Astral Construct comes with at least 1 menu option. Want a flyer? Done. Want a climber? Done. Want a Construct with the feat Whirlwind Attack to be in position right now? Done. Want Astral Construct Power Armor? I assume it works (http://brilliantgameologists.com/boards/index.php?topic=10279.0).
Astral construct is probably the power that has the most supplemental materials printed for it - not just on this list, but ever. (Link (http://www.minmaxboards.com/index.php?topic=15897.0)) Theoretically, you could be manifesting level 9 Astral Constructs by character level 6. That's like casting a super versatile level 9 summon spell spontaneously a number of times per day at character level 6! Even if your Astral Constructs are of a lesser optimization level, astral construct is the 'summoning' power of 3.5. Pretty much any challenge can be overcome with an imaginative and vigorous use of astral construct (http://8bittheater.wikia.com/wiki/Episode_986:_1/64).
Greetings, all!
I've pondered long and hard about 3.5's psionics. Which powers are the most powerful for a Psion? (That is, their effect is powerful and versatile on its own, but can also combine with other abilities and items for synergy.)
Assumptions
The following list of powers assumes the character has access to all of 3.5's material. I assume the a character has each power's 'accessories' - items, feats, races, etc. - that directly improve that power. These powers assume a Psion with a manifester level at least equal to his HD.
I also assume Complete Psionic's nerfs are not in place. Astral construct was probably hit the hardest by Complete Psionic wherein a manifester is limited to one Astral Construct at a time. Other casters, like Druids and Clerics and Wizards, have no such limit on the number of active summons.
Criteria for Judging
A power must be on the general Psion list or any Psion discipline list. I generally give preference to lower-level abilities since they're more likely to see play, and these powers have more metapsionic options available. It's easier to use Extend Power and Quicken Power on astral construct than fusion.
Beyond that, I consider what a power does on its own, what it couples with (like Metamorphic Transfer for metamorphosis), and how easily a character/player can use this ability to its fullest. How frequently is this ability useful, and how useful is it? How simple is this ability to understand?
Why make this list?
Because I was pondering this before bed and wanted to write it down for the world to enjoy! I also wanted to hear the opinions of others.
Runners Up
Runner Up Alpha: Forced Dream (Magic of Eberron).
Manifest forced dream, then while the power's duration hasn't yet expired, the subject may spend a swift action to undo all the actions that happened since the start of its turn. (PP spent to manifest forced dream are not restored, and spending a swift action to restart the turn ends the power.)
Forced dream is basically a one-time do-over - especially useful in situations where you know something dangerous is ahead, but don't know just what. Did the antagonist just shrug off your energy missile? Did a trap leave your party trapper hurtin'? Did you say the wrong thing in a social situation? Was someone hit by an attack of opportunity? Did the subject fail a crucial roll, like an accuracy roll or a skill check? Try again!
Runner Up Beta: Energy Missile (http://www.d20srd.org/srd/psionic/powers/energyMissile.htm).
Energy missile is a level 2 Kineticist, Medium range power that can hit up to 5 separate targets, each up to 15' apart. When you absolutely want to blast, this is the go-to power. And any full manifester can learn this power via Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge[/url) as soon as level 5!
It's the lowest-level multi-target power that doesn't require augmenting to affect more than 1 target. It also targets Fortitude (cold damage) or Reflex (fire, electricity, or sonic). You can deal more damage directly with cold or fire, increase your DC with electricity, or hurt pretty much anything with sonic. Sure, it's power point inefficient compared to buckets of Black Lotus poison (see below), but it's probably the best targeted damage power there is.
I prefer to ignore the Complete Psionic nerfs to this power. (This power becomes notably weaker with them.) Ask your GM what he thinks.
Runner Up Gamma: Temporal Acceleration (http://www.d20srd.org/srd/psionic/powers/temporalAcceleration.htm).
As a swift action, gain another turn. It's a psionic, 1-round (but augmentable for more!) version of time stop (http://www.d20srd.org/srd/spells/timeStop.htm) available at character level 11.
This is quite powerful, but hampered by 2 main drawbacks. First, anticipatory strike (Complete Psionic) exists and does a similar (nae, better) thing as a level 5 power instead of a level 6 power. Second, temporal acceleration renders the target Shaken at the end of it. Find a way to become immune to Shaken (like from being Undead or otherwise immune to fear) and you can spam this power!
Runner Up Delta: Fusion (http://www.d20srd.org/srd/psionic/powers/fusion.htm)/Mind Switch (http://www.d20srd.org/srd/psionic/powers/mindSwitch.htm) (Tie).
Fusion lets you combine yourself with another willing creature of your size category or smaller. Then manifest this power and do it again. And again. And again. Nothing in the power's description prevents you from doing this. Just be mindful of the 50 XP cost each time - a proverbial drop in the bucket at level 15+.
Fusion works best when combined with astral seed (http://www.d20srd.org/srd/psionic/powers/astralSeed.htm) and form-altering abilities like metamorphosis (http://www.d20srd.org/srd/psionic/powers/metamorphosis.htm) to give yourself a more permanent version of what you turned or/and fused into. (You need to manifest astral seed, die within 30 days, then wait 10 more days to grow a new body. You also lose a level.)
Meanwhile, mind switch lets you - also for an XP cost per manifestation - switch minds (and therefore bodies) with another subject within range. It's a lower-level solution (mind switch is a level 6 Telepath power opposed to fusion which is a level 8 Egoist power) and one native to Telepaths, but produces a similar effect: You have a spiffy new body. Yes, astral seed still also works. Yes, you can use this to take control of diplomats and authority figures and cause chaos.
Runner Up Epsilon: Psionic Minor Creation (http://www.d20srd.org/srd/psionic/powers/minorCreationPsionic.htm).
Psionic minor creation is a power that any character (even your Psicrystal!) can learn at level 1 via the feat Hidden Talent (Expanded Psionics Handbook), assuming the character has at least 11 CHA. Any manifester capable of manifesting level 2+ powers can spend a feat upon Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge[/url) and learn this power as soon as level 3 - assuming they don't know it already!
Manifesting this power probably requires a Craft skill check to make anything complicated enough to warrant a Craft check. (GMs, I recommend using this rule.) Still, being able to make buckets of Black Lotus plants (which you can turn into poison later if it isn't in poison form already) is still spiffy. You can also make less lethal items like ropes and ladders, but c'mon. Did you really learn this power for reasons besides making buckets of poisons?
Combine with Linked Power (Complete Psionic) to reduce the 10 minute manifesting time to 1 round.
Runner Up Zeta: Psychoport ('Psionic Teleport') (http://www.d20srd.org/srd/psionic/powers/teleportPsionic.htm).
Simple. Straightforward. Move from place A to place B (preferably with your party) as a standard action. No somatic nor verbal component. This level 5 Nomad power (also obtainable with (Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge)) lacks the guaranteed accuracy of the generally-available level 8 psionic greater teleport, but is available as soon as level 9 for Nomads!
Use this power to warp 100 miles per manifester level per manifestation. It's the ultimate mid-level get-in or getaway power!
Finally, teleport and psychoport are some of my favorite abilities. Plane shift is up there too. (Yes, I'm biased. I like to explore rapidly and laugh as others can't touch me. Ha-ha-ha-ha-ha-ha.)
The Winners
#5: Psychic Reformation (http://www.d20srd.org/srd/psionic/powers/psychicReformation.htm).
In short, you can change the feats, skill ranks, and powers known of yourself or a willing ally - with a 10 minute manifest time* and 50 XP spent per HD of change. (That's a maximum of 1000 XP for a level 20 character. No biggie!)
Psychic reformation is on this list due to its potential power. Want to be a blaster instead of a mind controller today? PsyRef! Want to make an ally suddenly an expert in this weapon type he just found? PsyRef! Want to learn some item creation or metapsionic/metamagic feats then swap 'em out when done? PsyRef!
*Add Linked Power (Complete Psionic) on PsyRef linked to a power with a shorter manifest time - like, oh, catfall (http://www.d20srd.org/srd/psionic/powers/catfall.htm) - and suddenly you're swapping builds as a standard action (or, with catfall, an immediate action) with 1 round of delay!
#4: Anticipatory Strike (Complete Psionic).
It's a level 5 Psion power that lets you, as an immediate action, take another turn. You may only use this power once per round, and it uses your swift action from your next turn, but oh golly! What can you do with an extra round of actions? Perhaps manifest a power from this list!
Anticipatory strike is the power from this list that has the least extra support. It doesn't need it.
#3: Synchronicity (Complete Psionic).
Synchronicity is a level 1 Psion power from Complete Psionic that lets you "ready a standard action (without spending an action to do so) and use it whenever you choose before your next turn." It has a 2PP augment which lets you ignore the 'you must declare what action you are readying' clause and just take a standard action.
On its own, synchronicity is OK - perhaps even balanced. Let's not consider this in a vacuum. You can use Linked Power (Complete Psionic) to give yourself extra standard actions. Yes, that's as powerful as it sounds. Want to make it even more delicious? Couple Linked Power with Metapower (Complete Psionic) to reduce the PP cost by 2.
-Manifest sense danger (Magic of Eberron) coupled with synchronicity to, for 10 minutes per manifester level, get an extra standard action at the start of each combat.
-Manifest schism (http://www.d20srd.org/srd/psionic/powers/schism.htm) and make your second mind manifest synchronicity every turn, then use the action from synchronicity to manifest another power at full manifester level. (Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge) can get you schism at character level 9, but you'll probably want to hold off on that until level 12.)
-Apply Twin Power (http://www.d20srd.org/srd/psionic/psionicFeats.htm#twinPower) or/and Quicken Power (http://www.d20srd.org/srd/psionic/psionicFeats.htm#quickenPower) to synchronicity. Applying both requires 2 psionic focuses, like from Psicrystal Containment (http://www.d20srd.org/srd/psionic/psionicFeats.htm#psicrystalContainment). (AmberVael mentions the difficulty of actually using two readied actions here (http://www.giantitp.com/forums/showsinglepost.php?p=19446047&postcount=18). Ask your GM.)
-Manifest psionic contingency (http://www.d20srd.org/srd/psionic/powers/contingencyPsionic.htm) with a fully-augmented synchronicity, possibly with Twin Power (http://www.d20srd.org/srd/psionic/psionicFeats.htm#twinPower) attached, with the triggering condition being 'when I want this to trigger.' Augment synchronicity as desired.
The main reason synchronicity isn't ranked higher on this list is because, on its own, synchronicity costs PP for potential. You could sniff your finger as a standard action (usually a waste), or make a single attack, or manifest a power, or cast a spell, or... The true power of synchronicity also requires you couple it with something else, especially Linked Power. Without these or similar ways to get extra standard actions, synchronicity is forgettable.
#2: Metamorphosis (http://www.d20srd.org/srd/psionic/powers/metamorphosis.htm)/Greater Metamorphosis (http://www.d20srd.org/srd/psionic/powers/metamorphosisGreater.htm) (Tie).
The Polymorph Handbook (http://www.minmaxboards.com/index.php?topic=519.0) forms a good basis for why this series of powers is in the #2 spot. Unlike the polymorph series of spells, metamorphosis is self-only, allows you to turn into objects, and the Overchannel (http://www.d20srd.org/srd/psionic/psionicFeats.htm#Overchannel) feat (and other means of boosting your manifester level) lets you assume forms of a higher HD total than your HD. And any Psion, Wilder, Erudite, or full manifester can take Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge) at character level 9 to learn metamorphosis. That's rad!
Wanna know what else is rad? Metamorphic. Transfer. (http://www.d20srd.org/srd/psionic/psionicFeats.htm#metamorphicTransfer) Requires 13 WIS (which you're gonna have anyway if you're going the Thrallherd route due to the Inquisitor (http://www.d20srd.org/srd/psionic/psionicFeats.htm#inquisitor) feat prereq) and manifester level 5. In exchange, you can use 3 supernatural abilities per day from any form you assume. Oh look! A Choker (http://www.d20srd.org/srd/monsters/choker.htm)! Oh look! A Hydra (http://www.d20srd.org/srd/monsters/hydra.htm)!
Greater metamorphosis is basically a better version of metamorphosis + Metamorphic Transfer in the form of a single power. It's also a level 9 power - putting it near the end of the expected campaign and into the 'very nice if you get there, but largely theoretical' territory.
#1: Astral Construct (http://www.d20srd.org/srd/psionic/powers/astralConstruct.htm).
This was a close call with the metamorphosis line of powers, but no other power provides such tremendous versatility and combat ability - from level 1! It's also a power that any character (even your Psicrystal!) can learn at level 1 via the feat Hidden Talent (Expanded Psionics Handbook), assuming the character has at least 11 CHA. Any manifester capable of manifesting level 2+ powers can spend a feat upon Expanded Knowledge (http://www.d20srd.org/srd/psionic/psionicFeats.htm#expandedKnowledge[/url) and learn this power as soon as level 3 - assuming they don't know it already!
Each Astral Construct comes with at least 1 menu option. Want a flyer? Done. Want a climber? Done. Want a Construct with the feat Whirlwind Attack to be in position right now? Done. Want Astral Construct Power Armor? I assume it works (http://brilliantgameologists.com/boards/index.php?topic=10279.0).
Astral construct is probably the power that has the most supplemental materials printed for it - not just on this list, but ever. (Link (http://www.minmaxboards.com/index.php?topic=15897.0)) Theoretically, you could be manifesting level 9 Astral Constructs by character level 6. That's like casting a super versatile level 9 summon spell spontaneously a number of times per day at character level 6! Even if your Astral Constructs are of a lesser optimization level, astral construct is the 'summoning' power of 3.5. Pretty much any challenge can be overcome with an imaginative and vigorous use of astral construct (http://8bittheater.wikia.com/wiki/Episode_986:_1/64).