Gayne is good attacker and buffer, which is notable due to Earth's lack of non-limited party buffers. Due to her high Double Attack rate and high damage cap on her nuke (~400,000) she can be used even in later parts of game despite being SR.
How to Play
Tribal SwordAll allies gain 15% ATK UpATK is boosted Strength: 15%Duration: 3 turns. At level 45: Buff increased to 20% ATK UpATK is boosted Strength: 20%Duration: 3 turns. At level 90: All allies also gain 20% DA UpDouble attack rate is boosted Strength: 20%Duration: 3 turns. is equivalent to Rage II, but with additional DA Up for whole party. These buffs are single-sided, so even if stronger Atk Up buff is on (e.g. Rage III) DA Up will still be applied.
KhashmalGain Dodge AllTakes no DMG or debuffs while in effect Duration: 1 turn . At level 65: Also gain 10% DA UpDouble attack rate is boosted Strength: 10%Duration: 3 turns. is used for dodging enemy Charge Attack, DA Up is just a bonus. EMP Support Skill makes Khashmal an additional nuke.
Sword Dance400%-500% Earth damage to a foe (Damage cap: ~420,000). is a simple nuke with a damage cap ~400,000, that is high for SR character. At 5★, using it after her Charge Attack casts this skill twice making her deal even more burst damage.
Synergy
Gayne doesn't require any setup, she is self-sufficent. She can fit any team as she brings a decent buff and deals solid amount of damage.
Higher levels of EMP Support Skill doesn't increase damage greatly, so it's recommended to leave it on level 1 (need verification).
Like every character's Critical Hit Perks, it is worth investing in when using the character on-element.
Additional points can be used on Attack Perks, Double Attack Perks (2*) and Overdrive Attack Perk. If survivability is needed it's recommended to invest points into DEF rather than HP.