| Ability | Effect | Requires |
| Alchemy | Doubles potency of item | Healing Water x4 |
| Break Damage Limit | Allows damage over 9999 | Dark Matter x30 |
| Capture | Capture fiend for the Arena | N/A |
| CounterAttack | Strike back after physical attack | Friend Sphere |
| Dark Touch | Sometimes add dark to attack | Smoke Bomb x20 |
| Darkstrike | Always add dark to attack | Eye Drops x60 |
| Double Overdrive | Charges gauge x2 faster | Underdog's Secret |
| Death Touch | Sometimes add death to attack | Farplane Shadow x30 |
| Deathstrike | Always add death to attack | Farplane Wind x60 |
| Double AP | AP x2 | Megalixir x20 |
| Evade & Counter | Evade then counter attack | Teleport Sphere |
| Firestrike | Adds fire to attack | Bomb Fragment x4 |
| First Strike | Act first in battle | Return Sphere |
| Gillionare | Doubles Gil earned | Designer Wallet x30 |
| Half MP Cost | Reduces MP use by half | Twin Stars x 20 |
| Icestrike | Adds ice to attack | Anartic Wind x4 |
| Initiative | Raises preemptive rate | Chocobo Feather x6 |
| Lightningstrike | Adds lightning to attack | Electro Marble x4 |
| Magic +10% | Magic power + 10% | Black Magic Sphere |
| Magic +20% | Magic power + 20% | Supreme Gem x4 |
| Magic +3% | Magic power + 3% | Mana Sphere x3 |
| Magic +5% | Magic power + 5% | Mana Spring |
| Magic Booster | Use MP to boost attack | Turbo Ether x30 |
| Magic Counter | Strike back after Magic attack | Shining Gem x16 |
| No AP | No AP gained | N/A |
| One MP Cost | Reduces MP use to one | Three Stars x20 |
| Overdrive->AP | Earn AP instead of Overdrive | Door to Tomorrow x10 |
| Piercing | Good against armored enemies | Lvl 2 Key Sphere |
| Poison Touch | Sometimes add poison to attack | Antidote x99 |
| Poisonstrike | Always add poison to attack | Poison Fang x24 |
| SOS Overdrive | Gauge x speed when low on HP | Gambler's Spirit x20 |
| Sensor | View Enemy data | Ability Sphere x2 |
| Silence Touch | Sometimes add silence to attack | Echo Screen x60 |
| Silencestrike | Always add silence to attack | Silence Grenade x20 |
| Sleep Touch | Sometimes add sleep to attack | Sleeping Powder x10 |
| Sleepstrike | Always add sleep to attack | Dream Powder x16 |
| Slow Touch | Sometimes add slow to attack | Silver Hourglass x16 |
| Slowstrike | Always add slow to attack | Gold Hourglass x30 |
| Stone Touch | Sometimes add petrify to attack | Petrify Grenade x10 |
| Stonestrike | Always add petrify to attack | Petrify Grenade x60 |
| Strength +10% | Attack power + 10% | Skill Sphere |
| Strength +20% | Attack power + 20% | Supreme Gem x4 |
| Strength +3% | Attack power + 3% | Power Sphere x3 |
| Strength +5% | Attack power + 5% | Stamina Spring x2 |
| Triple AP | AP x3 | Wings to Discovery x50 |
| Triple Overdrive | Charges gauge x3 faster | Winning Formula x30 |
| Waterstrike | Adds water to attack | Fish Scale x4 |
| Zombie Touch | Sometimes add zombie to attack | Holy Water x70 |
| Zombiestrike | Always add zombie to attack | Candle of Life x30 |
Final Fantasy X & X-2 on the forums...
Hi folks, posted this in the general discussion... then realised it was probably quite out of place there! 
I imagine there's probably
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