Your favorite/most successful Debuff spells

[Ignominia]

Ok Gang, Im playing a wizard whos focusing on debuffing in an upcoming game, and what Id like is a list of your favorite/most successful debuffs,(from any first party WotC published material) organized by level,save they effect and if its a single or group effect. It would also be super helpful to have the school of the spell (Im playing a specialist and haven't decided what schools to abandon yet)

Something like this:
1st-ray of enfeeblement(necro)-no save-single
2nd-blindness/deafness(necro)-fort-single
2nd-glitterdust(conj)-will-group

I want to make sure that if I have spells that allow saves, I have one for every occasion ready.

SO! Hit me with your favorites! We are starting at first level and are playing to about 10th, so about 5th-6th level spells would be my cap, but Im interested in seeing spells of all levels!

Thanks in advance!

[Umbranar]

May or may not be debuff but its crowd control atleast.

Web (level2) save and suck area - immobilized or hampered movement.
Grease (level 1) save and partially suck for most in area - flat footed if fewer than 5 ranks in balance, potentially prone.
Feeblemind (level 5 -4 to safe for arcanists) - int and cha become 1, cant cast spells
Solid Fog (level 4) no save and suck - only 5 ft move per action
Wall of Smoke (Spell Compendium level 1) save or nauseated blocks LoS

and many more I can not think of right now.

[tiercel]

If you include battlefield control as part of debuff then Umbranar is certainly hitting some high points. Honestly just Core Conjuration spells are huge in this regard, especially given that a number of them have a significant effect even if a save is allowed and passed.

Grease is multifunctional, since you can use it as "ranged trip," "ranged disarm," or "protection from grapple." If you use the "trip" application, note that a victim who successfully saves is still being forced to make Balance checks (which makes you flat-footed (http://www.d20srd.org/srd/skills/balance.htm) unless you have 5 ranks).

Glitterdust is both AoE blindness and AoE-breaks-invis/hiding. Only the former is affected by a save.

Web is sick, insofar you almost don't care if your victims make their save (given the rules for how hard it is to move even with a successful save). (This makes it one of the handful of attack spells actually worth spamming out of scrolls/wands.)

Stinking cloud is pretty much save-or-lose, and if they DO save, they still have lost line of sight (something you can use obscuring mist or fog cloud for by themselves at lower levels).

Solid fog not only blocks LoS but greatly slows opponents with no save, making it harder from them to escape the other effects you're spamming on them.

Black tentacles also has no save, instead grapple checks, to lock down and damage foes. Against foes with poor grappling/defense against grappling, this can be lethal alone; even against better grapplers, it can hold them in place for a lockdown combo (forcing several saves against a single effect).

Also every single spell of these is SR: No.

At mid-levels you'll definitely want dispel magic (and its variants) against spellcasting foes, because any time you face a BBEG with significant buff-stacking tearing down at least some of those buffs is a big boon. (Moreso if your foe is buffing with potions and/or scrolls, which often have a garbage caster level.)

A lot of people look down on Enchantments since they are pretty much all Mind-Affecting and target Will saves... but they tend to be of the "save or just lose" variety, so it's handy to have a few around if you haven't dumped the whole school.

Many Illusions aren't technically debuffs but can be ways to wrong-foot your opponents, whether it's gaining a surprise round on them or getting them to waste actions against figments.

[Silva Stormrage]

One of my favorite combos is web + stinking cloud. It is devastating if used against a party that can't teleport/has freedom of movement.

[Kuulvheysoon]

Web and creeping darkness (a Wu Jen spell). Creeping darkness makes anyone in the cloud blind, deaf, and unable to speak. Best part? No save/SR.

[Re'ozul]

While mechanically not the best, I love Unluck for the fluff.
Collapse the wave function the worse way.

[blelliot]

Ray of clumsiness is a fun one. Also I'm a big fan of wave of grief.

[eggynack]

In the line of solid fog, frigging freezing fog. It's like, you take a regular old solid fog, and you add grease, and suddenly all of these old things are made new again. Your enemies will be tripping over themselves trying to move even five feet. It also does 1d6 damage a turn, which is just a little bonus that you get for casting amazing spells. The reason it's so great is that it's essentially synergistic with itself. You cast it, and in the right situation, the battle is basically over. No save, just lose.

[Raimun]

Spell Vulnerability.

You know how all the monsters that you want to magic to death have spell resistance and that's a problem since that prevents you from magicing them to death? This spell helps.

[gr8artist]

Ask if you can import PF spells.
Sirocco (http://www.d20pfsrd.com/magic/all-spells/s/sirocco)- Lvl 6 - Fort part, SR: Yes
Downdraft knocks creatures out of the air, fatigues, and deals some damage. Remains for 1 rnd/level.

Call the Void (http://www.d20pfsrd.com/magic/all-spells/c/call-the-void) - 3 - Reflex part, SR: Yes
Sucks all the air out of the adjacent spaces, dealing damage and preventing speach. Failed saves earn your victims the fatigued condition.

Limp Lash (http://www.d20pfsrd.com/magic/all-spells/l/limp-lash) - 2 - SR: Yes
Makes a whip, ranged touch out to 20'. If you hit, victim takes 1d6 penalty to all physical ability scores per round until paralyzed. You just gotta hold on.

[Deaxsa]

one of my favorite debuffs is every single buff ever. why? they are relative debuffs, and they usually don't ask for a save or even spell resistance.

that said, slow/EBT/wall spells are all great debuffs/battlefield control spells (especially the wall spells, there is so much you can do with those)