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Cogidubnus
2010-04-24, 10:06 AM
I just ran the first session of a new 3.5 campaign. Started at level 7, with a fighter2/barbarian 5, a ranger2/rogue 5, a fighter 7 and a cleric 3/wizard 3/mystic theurge 1. None of the encounters were horrifically hard, but the lowest was CR 6. Most were 7-9. Yet they tore through them. One encounter, they killed a bearded devil outright in the surprise round, and lowered the mephits to1 HP each. The only thing that challenged them was the Vampire Drow Ranger, who spent most of his time leeching CON from the barbarian. Incidentally, the Mystic Theurge isn't the reason for this. His contribtion consisted mostly of using burning hands on low HP enemies and healing. Any advice?

The Rabbler
2010-04-24, 10:12 AM
how do you want it to be more challenging? do you want them to have a harder time killing the creatures? do you want the creatures to have an easier time killing your players? both?

if the former, throw in stuff with lots of hp and hot very high damage. advanced trolls are nice for this.

if the creatures are lacking in damage, you might want to try and use some meaner monsters. I find hydras to be a very simple way of doing this. throw on a few templates and you've got yourself a real challenge.

if both, make a well-built wizard NPC and have him toy with them while his summons or mooks finish the players off.

AmberVael
2010-04-24, 10:15 AM
Killed a Bearded Devil in one round, you say?
It's a CR 5 enemy. It's only got 45 hp, and these guys are level 7. I'd be ashamed of a group that couldn't do that. Frankly, the Fighter/Barbarian, or the Fighter, properly built, could have done that on its own.

Just from hearing the little you've said, my guess is that you're simply not making the encounters challenging enough, and underestimating the capabilities of a level 7 party. A level 7 party will easily defeat CR 7 encounters, and encounters of lower CR won't even be worth mentioning. I know why you're making this mistake, because it's a pretty easy one to make... the CR system doesn't quite work how people think it does.

Also, if you're tossing a bunch of lower CR monsters in to try and make challenges for this party (mephits? Bearded devil?) then it'll be even easier. I don't care how many CR 3 creatures you have, it's not going to be a challenge for a level 7 party.

My advice is:
Up the CR of individual creatures. Throw less creatures at them, but ones of higher CR. If you want a big boss, make the big boss CR 10 or 11. That will give them a challenge.


And incidentally, I'm not surprised that the mystic theurge wasn't a problem. They're notoriously weak.

DarkEternal
2010-04-24, 10:20 AM
Toss in a few basilisks. It's CR 4 I think and yet, many evil laughs of the DM will be heard.

Yora
2010-04-24, 10:29 AM
I just ran the first session of a new 3.5 campaign. Started at level 7, with a fighter2/barbarian 5, a ranger2/rogue 5, a fighter 7 and a cleric 3/wizard 3/mystic theurge 1. None of the encounters were horrifically hard, but the lowest was CR 6. Most were 7-9. Yet they tore through them. One encounter, they killed a bearded devil outright in the surprise round, and lowered the mephits to1 HP each. The only thing that challenged them was the Vampire Drow Ranger, who spent most of his time leeching CON from the barbarian. Incidentally, the Mystic Theurge isn't the reason for this. His contribtion consisted mostly of using burning hands on low HP enemies and healing. Any advice?

If you want fights to be harder, use tougher monsters. Even if the EL rises to 8-10 or higher, as long as the fight is appropriately challenging, it's fine.
But you might want to reduce the amount of XP the party gets, or they will need a lot less than 13 encounters to get a new level.

Cogidubnus
2010-04-24, 10:51 AM
Thanks. I guessed the problem was something to do with the CR system. And to be more precise, the Bearded Devil went down to one hit from the barbarian. Part of the reason for lower CR monsters is that the encounter systme as explained means that it's quite hard to get an encounter with more than one monster. I'll try upping the CR but leaving XP the same. That ought to make things tougher. I do still wonder though. I mean yeah, lower level monsters will never be as much of a challenge, but that fact that it's this easy for them is a little worrying. I've mostly DMed 4e in the past, and that allows for slightly larger encounters while keeping a balance. I've got a high level druid coming up, who I'm hoping will challenge them, if druids really are so broken.

AmberVael
2010-04-24, 10:55 AM
Well, you're playing with a horrifically unoptimized party from what I can see (fighter? Fighter/barbarian? Mystic Theurge?), so all I can say is that if something is wrong, it's not on the end of your party. More likely, it has to do with the creatures you're tossing at them, or the strategy these creatures use.

Try throwing Animals at them- both regular and Dire. That might help. Your group is obviously focused straight combat (except for the theurge, but he's focused on fail at this low level), so making something that challenges them in another way would be kind of cruel... but animals are like, pure HP and heavy attacks, and lower CR because of their single minded focus, so it might work well.

Cogidubnus
2010-04-24, 11:22 AM
Ok. The Theurge, while weak, does do the job he needs to, which is buffing. I'll try animals. Anything with high HP will help. High AC seems to make very little difference, as most of them have between +10 and +15 to attack rolls. Similarly, it's hard to even scratch them. The fighter has AC 25, the barbarian's forfeited Fast Movement for full plate and has AC 21.

Oslecamo
2010-04-24, 11:26 AM
Check out myguide for DMs to building challenging ecounters. (http://www.giantitp.com/forums/showthread.php?t=133604) Not finished but plenty of advice.

BtanH
2010-04-24, 11:28 AM
Ok. The Theurge, while weak, does do the job he needs to, which is buffing. I'll try animals. Anything with high HP will help. High AC seems to make very little difference, as most of them have between +10 and +15 to attack rolls. Similarly, it's hard to even scratch them. The fighter has AC 25, the barbarian's forfeited Fast Movement for full plate and has AC 21.

Meh, 25 AC shouldn't be that bad, just throw in some monsters with class levels or spell like abilities (charm person anyone?). Animal are a good idea. So are giants (high HP low AC)

Cogidubnus
2010-04-24, 11:32 AM
Got a giant planned. Was thinking I need abilities, particularly those that target will, for more challenging encounters.

Nidogg
2010-04-24, 11:41 AM
Throw in encounters to serously muck things up. Mellee ers stealing the limelight? Toss incorperal enemys in there. Casters the problem? Put Int/Wiz/ Cha (Casters primary) drain or spell eaters (from dragon magic). Or. Have them fight THEMSELVES Alter race, specis, gender and maybey re-arange a few things so It doesnt become imediatly obvious that your in a Famed Mimic Gogo (http://www.youtube.com/watch?v=60rrxYfuQPk) situation.

BtanH
2010-04-24, 11:51 AM
1 Succubus should be enough for a looooong time.
Kinding... just trow them a 1st level wizard riding a giant. Should work out ok.

TheCountAlucard
2010-04-24, 01:56 PM
Don't just go animals. Go half-dragon animals.

What's scarier than a bear? A super-bear that flies and is immune to fire.

Cogidubnus
2010-04-24, 03:47 PM
Think I've mentioned this before, but the one encounter that did work was the vampire. Between CON drain and negative levels, he nearly killed the barbarian. And they've got to fight him again (he fled to his coffin while they rested), so I might up his HD a bit to make the difference. His attack bonus is enough to land hits too.

Gnomo
2010-04-24, 04:09 PM
Pick up a low level enemy and advance it.

================================================== ===============

Lets say the classic serpentine Grick (http://www.d20srd.org/srd/monsters/grick.htm), this is how it would look like advanced a little bit:

Size/Type: Large Aberration
Abilities: Str 22, Dex 12, Con 16, Int 3, Wis 14, Cha 5
Hit Dice: 6d8 + 18 (49 hp)
Initiative: +1
Speed: 30 ft. (6 squares), climb 20 ft.
Armor Class: 16 (+1 Dex, +6 natural, -1 size), touch 10, flat-footed 15
Base Attack/Grapple: +4/+14
Attack: Tentacle +9 melee (1d8+6)
Full Attack: 4 tentacles +9 melee (1d8+6); bite +7 melee (1d4+3)
Space/Reach: 10 ft./10 ft.
Special Qualities: Damage reduction 10/magic, darkvision 60 ft., scent
Saves: Fort +5, Ref +3, Will +7
Skills: Climb +10, Hide 3, Listen +6, Spot +6
Feats: Alertness, Track, Multiattack, Improved natural attack (tentacle)
Environment: Underground
Organization: Solitary or cluster (2-4)
Challenge Rating: 5
Treasure: 1/10 coins; 50% goods; 50% items
Alignment: Usually neutral
Advancementt: 3-4 HD (Medium); 5-6 HD (Large)

Now with two of this monsters you have a CR 7 encounter.

================================================== ===============

If you want to give your party a harder time try the Formian Champion (http://www.d20srd.org/srd/monsters/formian.htm):

Size/Type: Large Outsider (Lawful Extraplanar)
Abilities: Str 26, Dex 14, Con 20, Int 10, Wis 12, Cha 10
Hit Dice: 12d8 + 60 (122 hp)
Initiative: +2
Speed: 40 ft. (8 squares)
Armor Class: 18 (+2 Dex, +7 natural, -1 size), touch 11, flat-footed 16
Base Attack/Grapple: +12/+24
Attack: Sting +19 (2d6+8 plus poison)
Full Attack: Sting +19 (2d6+8 plus poison) and 2 claws +17 (1d8+4) and bite +17 (1d6+4)
Space/Reach: 10 ft./10 ft.
Special Attacks: Poison (Injury, Fortitude DC 23, initial and secondary damage 1d6 Str. The save DC is Constitution-based)
Special Qualities: Hive mind, immunity to poison, petrification, and cold, resistance to electricity 10, fire 10, and sonic 10, spell resistance 18
Saves: Fort +13, Ref +10, Will +9
Skills: Climb +22, Hide +17, Jump +26, Listen +16, Move Silently +17, (+10 following tracks), Tumble +14, Spot +6
Feats: Dodge, Multiattack, Skill focus (poison), Combat Reflexes, Blind Fight.
Challenge Rating: 8
Alignment: Usually lawful neutral

Keep poisoning the players to take their Strength score down, this will scare them. Remember that this monster has a 10 ft. reach and Combat Reflexes, that's enough poisoning to everyone.

================================================== ===============

Now, if you want to add some madness into the mix, nothing say crazy like an incorporeal flying suicidal undead, the Allip (http://www.d20srd.org/srd/monsters/allip.htm).

Size/Type: Medium Undead
Abilities: Str -, Dex 12, Con -, Int 11, Wis 11, Cha 20
Hit Dice: 12d12 (62)
Initiative: +6
Speed: Fly 30 ft. (perfect) (6 squares)
Armor Class: 16 (+1 Dex, +5 deflection), touch 16, flat-footed 15
Base Attack/Grapple: +6/-
Attack: Incorporeal touch +7 melee (1d4 Wisdom drain)
Full Attack: Incorporeal touch +7 melee (1d4 Wisdom drain)
Space/Reach: 5 ft./5 ft.
Special Attacks: Babble (DC 23 Will save), Madness, Wisdom drain
Special Qualities: Darkvision 60 ft., incorporeal traits, +2 turn resistance, undead traits
Saves: Fort +4, Ref +8, Will +8
Skills: Hide +16, Intimidate +7, Listen +15, Search +12, Spot +15, Survival +0 (+2 following tracks)
Feats: Improved Initiative, Lightning Reflexes, Skill focus (babble), Fly-by attack,
Challenge Rating: 5
Alignment: Always neutral evil

Just use fly-by attack to drain wisdom and babble the party away. Two Allips make a CR 7 encounter, you can say that itīs a couple that killed themselves because their families didnīt let them be together, call them Ramon and Jeanette.

AmberVael
2010-04-24, 05:07 PM
Don't just go animals. Go half-dragon animals.

What's scarier than a bear? A super-bear that flies and is immune to fire.

DM: You see a large creature, brown furred and shambling towards you on four legs. Its mighty paws show frightening claws, and-

Player 1: We're fighting a bear?

Player 2: Laaaaame.

DM: Uh... and it has scales! And frickin' huge wings! It leaps into the sky and breathes fire at you!

AslanCross
2010-04-24, 05:40 PM
Thanks. I guessed the problem was something to do with the CR system. And to be more precise, the Bearded Devil went down to one hit from the barbarian. Part of the reason for lower CR monsters is that the encounter systme as explained means that it's quite hard to get an encounter with more than one monster. I'll try upping the CR but leaving XP the same. That ought to make things tougher. I do still wonder though. I mean yeah, lower level monsters will never be as much of a challenge, but that fact that it's this easy for them is a little worrying. I've mostly DMed 4e in the past, and that allows for slightly larger encounters while keeping a balance. I've got a high level druid coming up, who I'm hoping will challenge them, if druids really are so broken.

Use an encounter calculator. (http://legionofgeeks.com/encounter_calc.php)

This has allowed me to build fairly complex groups of encounters with multiple grunts and one or two heavy bruisers, sometimes with a caster in the mix.

Also, use terrain. Don't use boring old flat cubic rooms where everyone is in direct line of sight. Have pillars for obstructing line of sight/line of effect, elevated platforms out of the reach of melee bruisers, monsters hanging from chains above the PCs, difficult terrain, and even hazards like lava chasms where the PCs can fall to their death.

Interactive environments, such as movable furniture, levers that cause jets of fire to shoot out of walls, etc. can prove to be memorable and useful.

Magic Myrmidon
2010-04-24, 05:48 PM
Use an encounter calculator. (http://legionofgeeks.com/encounter_calc.php)

^ That.

This one gives CR and average gold. It's not bad. A friend showed it to me.

http://www.penpaperpixel.org/tools/d20encountercalculator.htm

Gnaeus
2010-04-24, 06:07 PM
Be REALLY careful with the up the CR and throw animals at them advice.

You have a low optimization party. You do probably need to raise the CR level a little bit, but the danger is that you can easily wind up with creatures that can 1-shot your guys, which is bad, or that have such high AC that they can't be hit, which is worse if your party is 3 mundane attackers and a healer/buffer.

A CR 10 encounter for a 7th level party should be tough, but doable, for example. A CR 10 encounter with animals is like 2 dire tigers. 2 Dire Tigers would Pounce/Grapple the fighter and barbarian in round 1 (maybe kill one of them if they roll a crit), and almost certainly kill them both in round 2, then munch on the squishies.

Not saying that the advice you are getting is wrong, just be careful with it.

Cogidubnus
2010-04-25, 08:32 AM
I keep quite a close eye on damage outputs. And to be fair, its seems a CR10 encounter made of lower-CR creatures ought to be perfectly feasible. I mean, they finished off a CR9 of 3 monsters with 4 attacks. The straight fighter didn't even get a round. What I need are monsters with high HP and either SLAs or high bonuses to the attack rolls. Which is why the vampire worked, I think. He didn't need to hit their armour, just grapple and pin to do CON damage, and his bonuses to attack rolls were enough to get through their AC anyway. As for the bloodsucking, it gained him temp HP which allowed him to take hits on the chin. Next time, I'll have him cast darkness and then pounce the rogue. Ought to cause some panic.

AslanCross
2010-04-25, 09:15 AM
I keep quite a close eye on damage outputs. And to be fair, its seems a CR10 encounter made of lower-CR creatures ought to be perfectly feasible. I mean, they finished off a CR9 of 3 monsters with 4 attacks. The straight fighter didn't even get a round. What I need are monsters with high HP and either SLAs or high bonuses to the attack rolls. Which is why the vampire worked, I think. He didn't need to hit their armour, just grapple and pin to do CON damage, and his bonuses to attack rolls were enough to get through their AC anyway. As for the bloodsucking, it gained him temp HP which allowed him to take hits on the chin. Next time, I'll have him cast darkness and then pounce the rogue. Ought to cause some panic.

How much do your PCs deal? What were the monsters in that CR 9 encounter?

Lord Loss
2010-04-25, 09:41 AM
I had the same problem. I tried throwing more monsters at the PCs but itdidn,t quite cut it. The solution is this formula which works some of the time.

Challenging Fight (I have very, very tactically smart/ intuitive Players, so this may be too hard for your game, dun work at lower levels)

Total CR: (# of Players x PARTY LEVEL) +2. No individual monster may be equal or more powerful than 2x Party level.

So basically an appropriate fight for 4 lvl 5s is 4 CR 4s and 1 CR 6.

Superglucose
2010-04-25, 10:03 AM
When designing an encounter use real tactics. Archers should be hiding on top of a cliff or "Shot on the Run" ing to and from cover. Clerics should be buffed up and ready to go. Heck, even animals have the ability to use tactics (just look how wolves and tigers hunt).

One of the most successful encounters I ever ran was a boss fight of a CR 5 Troglodyte cleric and four CR 3 Troglodyte rangers (archery focused) against a party of 6 level 5 characters. Basically here's how it went:

The four archers ducked out of cover based on readied actions triggered by the cleric ("He's casting!" *jump out* *shoot casters*) and otherwise the Cleric just went toe-to-toe with the biggest of the bads he could find... using your typical cleric buffs to be pretty damn tough and strong. When the first Wind Wall came out, the troglodyte archers used the pillars to provide cover and move around the wind wall, and by the end there were three wind walls circling the center where the main meat had engaged the Cleric. Two of the four Trog archers were trapped in a web off to one side while another was flat out dead (caught a lightning bolt to the face), and the third was unable to get a shot and unwilling to close and enter the wind wall to get his shots off.

Eventually through action economy the Cleric fell... 10 rounds into combat.

Truth be told the guys in the party weren't in any real danger of dying (the damage output just wasn't that high) but they loved having to find solutions for the unusual tactic of being sniped from cover and enemies who were actually using their mobility to their advantage. Great fun was had all around.

Cogidubnus
2010-04-25, 10:12 AM
The cr 9 encounter wasn't really tough, monsters, just a bearded devil and two mephits, but as I said above, the devil went down to one punch. I've been toying with the mob rules and raising hd or levels. Monsters are looking tougher. Even raising a hobgoblin with ten levels in warrior (a cr 5 monster) is looking better. Giving him some good equipment makes him even more capable. More like the sort of low level monster I need.

Greenish
2010-04-25, 10:17 AM
The cr 9 encounter wasn't really tough, monsters, just a bearded devil and two mephits, but as I said above, the devil went down to one punch. I've been toying with the mob rules and raising hd or levels. Monsters are looking tougher. Even raising a hobgoblin with ten levels in warrior (a cr 5 monster) is looking better. Giving him some good equipment makes him even more capable. More like the sort of low level monster I need.In order to challenge your party, they're going to need great gear. Once the party defeats them (which usually isn't that hard to begin with) they will loot said gear and be that much more difficult to challenge next time around.

Cogidubnus
2010-04-25, 10:20 AM
The gear isn't the only boost. Just a small one to complement their raised levels. Mostly magic armour, as the party only missing on natural ones would make it hard to lose.

Yora
2010-04-25, 10:22 AM
The cr 9 encounter wasn't really tough, monsters, just a bearded devil and two mephits.
That's not CR 9, that's CR 7.

2 Mephits are 2 CR 3 creatures, which count as one CR 5 creature.
And 2 CR 5 creatures make an EL 7.

Now if you would double all this, you would end up with EL 9. But CR 3 and 5 creatures really won't challenge level 7 characters.
Better try one CR 7 creature and see what happens then!

Mephits attack with a luaghable +4, but a single CR 9 frost giant attacks with +18 and deals about 24 damage with every hit. A mephits 2 points of damage are nothing compared to that.

Cogidubnus
2010-04-25, 10:28 AM
Ok. miscalculations aside, this is what i've discovered. One high cr monster is considerably more of a threat.

Amphetryon
2010-04-25, 10:35 AM
4 Half-Dragon Quasits are within this party's CR, and between invisibility, alternate form, and 6d8 breath weapons, should confound and challenge the group without being instantly fatal.

Yora
2010-04-25, 10:53 AM
Even if a creatures CR is right, and quite often it's rather far off, masses of low level creatures suffer from the problems of low AC, saves, and attack bonus. Their low hp and low damage can partly be compensated by having more individual creatures, but when they become unable to hit or defend themselves against attacks from the PCs, this doesn't help them at all.

Cogidubnus
2010-04-25, 04:32 PM
The mob template designed by the guy who linked his dm's guide (Very impressive btw. Covered a lot of both what's been said here and my other thoughts) seem a good way to make hordes more effective. I've been making some trial ones and they seem to work. Units of hobgoblins have particularly potentially good stats.

AslanCross
2010-04-25, 05:07 PM
Ok. miscalculations aside, this is what i've discovered. One high cr monster is considerably more of a threat.

Not always. You could have a CR 10 Human Monk 10 and he'll be a completely different threat when compared to a CR 10 Red Dragon. The monk lacks a whole bunch of options when compared to the dragon, which has AOE attacks, spells, flight, and very high AC. It's also much easier to corner the monk as he's only human sized.

There's also the thing that CR almost never takes into consideration: Action economy. Four PCs will get to do four things per round; a single monster can only do one thing. If he's lucky he can get in a full attack or an AOE spell, but he is by default shafted in terms of what he can do.

There are times when multiple weak monsters can indeed challenge a high-level party. In my campaign, for example, against five Lv 10 PCs I threw four Skullcrusher Ogres (CR 5 each), two Whitespawn Berserkers (CR 6 each), and a Hobgoblin Fighter/Swordsage/Dervish (CR 8).

The shifter warblade in the party dashed forward to engage them and got mauled, taking 100 damage in the span on 1 round. Even if she could have theoretically taken down the ogres in one hit each, they kind of mashed her up. (Of course, her AC was really low at the time.)

Here's an example of how I design encounters. It's a bit of a spoiler for my campaign (2 Lv 11 PCs, 3 Lv 10 PCs), so I'll box it in.
The PCs reach the main barracks of the enemy stronghold. All of the soldiers inside are fiends: four Legion devils with a single rogue level (CR 4 each), a Mezzoloth (CR 6), and an advanced Chain Devil with Rogue 1/Fighter 1. (CR 10).

Terrain: The barracks has been mostly cleaned out of beds---fiends don't need to sleep---and the beds have been piled up on one end to use as a barricade versus the attacking PCs. Three young dead dragons hang from the ceiling via meat hooks on chains. The room is large, almost 100 feet long on its long axis, and is littered with overturned tables for use as cover. It's completely dark. The ceiling is 25 feet high.

Tactics: The legion devils stay behind cover, taking potshots with their bows. Their legion's skill ability increases their attack bonus to high enough to hit the PCs. The Mezzoloth hangs way back, and bombs the room with Cloudkill (the legion devils are immune to it.) The chain devil uses its Dancing chains ability to control the chains the dragon corpses are hanging from, climbing up to the ceiling (outside of the cloud of toxic gas; it's not immune to poison). It then uses the dancing chains ability to attack the PCs with the chains at ground level; considering that dancing chains can control chains up to 20 feet away and can cause them to extend 15 feet, the chain devil can theoretically attack enemies up to 35 feet away.
If the chain devil realizes it's getting beat on, it traverses the ceiling on the chains and hangs itself from the hooks (its DR and regeneration prevents the chains from really hurting it) so that it doesn't fall to the floor for the PCs to gang up on.

Development: The fiends have telepathy. Whatever the outcome here, the entire complex is going to be alerted within a minute.

Oslecamo
2010-04-25, 06:07 PM
The mob template designed by the guy who linked his dm's guide (Very impressive btw. Covered a lot of both what's been said here and my other thoughts) seem a good way to make hordes more effective. I've been making some trial ones and they seem to work. Units of hobgoblins have particularly potentially good stats.

Well thank you for the compliments! Indeed I would've sugested the mob and unit templates myself to make groups of mooks challenging but it's great to see you already checked them already!:smallbiggrin:

TheOverlord
2010-04-25, 10:01 PM
There are a ton of great ideas in this thread so I will try not to reiterate too much of what has already been said, but I will point out a few things I base my whole concept on...

1. Parties can vary drastically based on the party make-up knowing what type is a tough encounter for a given group takes time and finesse.

2. The CRs for creatures are not made to be adjusted based on the party's ability to fight it. A hydra is much harder to defeat vs. a party without a lot of ranged attacks or sunder feats but its CR is the same even if the group is 4 rangers with far shot or 4 beefed up barbarians with improved sunder.

3. Some parties just know how to deal damage...there are two ways to deal with this... more HP (advanced creatures whose CR does not increase rapidly), more SR (if the party uses magic), and larger creatures who can change how the battle can progress (teleport at will with the quickened spell-like ability feat or larger creatures with grappling)

4. With that said...the easiest way is to make your players consider the impossible. Not from a "My DM killed me twice in one night" way...but rather in a "My DM is imaginative and sneakier than hell" way. That's right, a DM's greatest power is imagination...and imagination equals players thinking about what may be or could be or has been. I advocate for generous use of Sun Tzu's teaching that says when the enemy expects one thing do another. If he expects an attack from the front attack from the rear. If you are strong make him think you are weak.

This whole debate and the questions you ask are 100% the reason I initially created the Monster Advancer (http://www.monsteradvancer.com) for my personal use. I needed stronger creatures with more interesting abilities and classes and I could no longer take several hours to do it without feeling like I had "stretch" or cheat on CRs.

With that said...the CR system is far from perfect and I not advocating trying to kill off your players at all, so I advise being careful the first few times you try adjusting creatures as it is easy to create creatures within the rules and within the CR you want that can easily devastate the party (how bad it is always depends on circumstances and the party's strengths and weaknesses).

An example of potential doom:
Try advancing a Tendriculos to 17HD (which is a Gargantuan creature) it only has a CR of 9...but it would TPK a large number of parties the first time out of the gate...and that is without giving it the grappling feats Snatch and Multi-snatch. Play test it if you are skeptical. I don't advise doing these sort of experiments to your actual parties.

The bottom line is get to know your party and be creative as well. There are tools out there to help push monsters the way they were meant to be...there is no longer any need for cookie-cutter creatures.