Make your own ability!

[Liam]

Special Shield

Any stat-ups you use that include Defence, Sp.Defence or HP are doubled.

[Poseidon]

Royal Guard

This Pokemon is immune to all status conditions (including Confusion).

[THE ARBITER]

grass blade icreases yourgrass atacks but weakens damage by fire type icreases all other weakneses

[Enigma]

Caterpillar Tracks

Restores health when switching a Pokemon with this ability into Spikes, Toxic Spikes or Stealth Rock. (e.g. if all three are on the field, they get 12% recovery from Spikes, 12.5% from SRocks, and something like 12.5% for Toxic Spikes.) Would be something that would perhaps reduce the SRock-centric metagame.

Bulldoze

When this Pokemon is brought into battle, all field effects are removed (fog, spikes, SRock, weather.)

Again, something that might make people think twice about using SRocks.

[Afro-Disiak]

i can't be bothered to look through 7 pages of  this thread, but here's an idea for an ability I'd like to see:

Magnifying Glass

Much like a Synchronizer, but for IVs when you lead this in battle, you either have a 50% chance of finding a pokemon with 1 of the same IVs as you, OR you have a 50% chance of finding something with a max IV in a certain stat (not sure which one though).

Would make breeding and ditto hunting a bit easier ;o

[Enigma]

i can't be bothered to look through 7 pages of  this thread, but here's an idea for an ability I'd like to see:

Magnifying Glass

Much like a Synchronizer, but for IVs when you lead this in battle, you either have a 50% chance of finding a pokemon with 1 of the same IVs as you, OR you have a 50% chance of finding something with a max IV in a certain stat (not sure which one though).

Would make breeding and ditto hunting a bit easier ;o

What would its in-battle effect be? I know it doesn't need to have one (e.g. Run Away,) but the IV-effect would be so vague for normal players...perhaps something along the lines of copying the foe's stat boosts (e.g. They use Dragon Dance, you get the boost too?) I was thinking double the boost (due to the whole magnifying part) but that could be a bit broken...switch it in against a Nasty Plotting Infernape...buahaha.

Loyalty

In Double Battles, attacks aimed at this Pokemon's partner will have a 50% chance of striking this Pokemon instead.

Something for Gardevoir or Lucario, I thought, considering their protective nature. Could be cool for letting a Slaking set up or something. Quite luck based though. :S

[Liam]

Power up

Every time a Pokémon with this ability restores more than 40% of HP (at one time) a random stat is increased.

LOL SPAM RECOVER

Sunblock

All moves that are changed by Sunny day only do their normal things. (Like Solarbeam doesn't attack straight away and fire moves aren't powered up.)

[Poseidon]

Heat Shield

This Pokemon is immune to Ice attacks.

Second Chance

Is revived with 1/16th of Max HP when knock out.

(Now that would be useful.)

[President Hawkeye]

Supercharge
Every kind of attack on the foe may paralyse it with 20% chance.

Time to Think
Two-turn attack has 10% more power. (E.g. Dive, Fly, Sky Attack, etc...)

Steam
A water-type attack may cause a burn with 10% chance.

Take 20 Paces
Attacks that take priority (E.g. Quick Attack, Bullet Punch, etc...) have increased power (10%), never miss, and negated Detect, Protect, Reflect and Light Screen.

Alarm Clock
Wakens immediately from Sleep.

Red-Dot Sight
Negates evasiveness changes by the opponent.

[Laprabi]

Aerodynamics
Flying-type attacks to 15% more damage.

Haste
On the first turn, the Pokemon which has this ability will always go first. If two Pokemon have this ability, then it will be judged by Base Speed.

[Alllister]

Defensive tactics

The pokemon is knowledgeable in defensive combat tactics and maneuvers, making the users defense, special defense, and evasion all effectively one stage higher.  In doubles, it affects both the pokemon with the ability, and it's partner(s).

[Poseidon]

Fury

[Pokemon]'s Attack and Sp. Attack stats rise one stage each turn in battle.

[Y2Jt]

Double Time
All moves have 25% chance to hit twice
(Imagine Frenzy Plant/ Blast Burn/ Hydro Cannon)

[Lightshock16]

Self-Recharge

Reduces Special Attack, but allows moves that need recharging to be used without the need to recharge.

[Poseidon]

Stone Skin

[Pokemon]'s Defense is doubled.

Crystal Scales

This Pokemon does not take damage from attacks with Base Powers over 100.

Man, that would be awesome on a Milotic or something.