By Siriusly Intrepid
This is from the FAQ post, however this list is in alphabetical order in case that helps you find the boost you are after easier!
While I can’t give specific numbers, this is just a variation of the descriptions to help with understanding:
Accuracy – Improved version of Precision. (Increases the accuracy of your hits (reduces misses)!)
Anticipation – Increases your chance of parrying your opponent’s hits.
Armour Penetration – Increases your hit power against opponents who use certain boosts to increase their armour.
Avoidance – Improved version of Evasion. (Increases your chance of dodging hits.)
Brute Strength – Increases the damage you do on attacking hits.
Calculated Strikes – Reduces the chance of being parried.
Cortez’s Medallion – Adds an extra coin to your standard rewards after battling.
Crushing Blows – Increases your chance of disarming your opponent.
Dark Bargain – Adds extra power to your attacks, but you also lose 9 health points each time you land a hit.
Deadly Aim – Increases your chance of critical hits.
Desperation – Gives a chance of very high powered attacks when at low health.
Evasion – Increases your chance of dodging hits.
Extra Health – Adds a small amount of health points to your total available.
Fear – Slows down your opponents attacks (i.e. reduces their chance to combo).
Heavy Hands – Gives more damage when fighting with your fists.
Improved Grip – Helps you hold onto all of your weapons / shields in battle, i.e. reduces your chance of being disarmed.
Knockback – Increases your chance of performing a Surprise attack when your opponent tries to attack!
Mark of Twilight – Chance to gain health on attacking hits. Also includes a rare chance to regain health once KOed.
Master Pugilist – Improved version of Pugilism. (Increases your amount of quick 1-2 punch combinations when fighting with your fists, and increases your chance of these being these critical hits.)
Midas Medallion – Adds an extra two coins to your standard rewards after battling.
Painful Strikes – Increases the damage you do with critical hits.
Painkillers – Gives a chance of reduction of damage taken on incoming hits.
Precision – Increases the accuracy of your hits (reduces misses)!
Protection – Significantly increases your armour which gives a reduction of damage taken on each incoming hit.
Protective Haze – Reduces your chance of receiving a critical hit.
Pugilism – Increases your amount of quick 1-2 punch combinations when fighting with your fists, and increases your chance of these being these critical hits.
Quick Thinking – Improves the speed of your planned attack which reduces your chance of being Countered.
Rage Attacks – Deals damage to your opponents when they critically hit you.
Reflect Damage – Gives a small reduction in your opponents health when they hit you.
Reflex Blocks – Increases your chance of blocking when using a shield.
Regeneration – Allows you to regain some health each turn.
Retaliation – Increases your chance of a Counter attack.
Sapping Aura – Reduces your opponent’s health by 4 every turn.
Shield Patch – Increases your shield strength so that less damage gets through.
Static Charges – Gives a chance of extra damage on your attacking hits.
Stone Hands – Improved version of Heavy Hands. (Gives more damage when fighting with your fists.)
Stonewall – Improved version of Reflex Blocks. (Increases your chance of blocking when using a shield.)
Super Grip – Improved version of Improved Grip. (Helps you hold onto all of your weapons / shields in battle, i.e. reduces your chance of being disarmed.)
Swiftness – Improved version of The Quickness. (Gives you chances of extra attacks (i.e. more hits in a row).)
The Quickness – Gives you chances of extra attacks (i.e. more hits in a row).
Thick Skin – Increases your armour which gives a reduction of damage taken on each incoming hit.
Unpredictability – Reduces the chance of your opponent when they have a shield equipped blocking your hits.
Unstoppable – Reduces the chance of a Surprise attack against you.
Vitality – Improved version of Extra Health. (Adds a small amount of health points to your total available.)
Web – “Reduces your opponents chance to dodge.” Please note that this affects dodges, not misses.

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