I hate to break it to all you guys in love with the speed bio but the best combo is the coma combo in psycho.
You automatically kill your opponent in six turns no matter how much health they have.
Abilities needed: two high voltage(only needs to be clicked once), 2 shock coma(3/3), retrograde(2/2), overdrive(1/1)
first use high voltage twice, then use shock coma twice, then another high voltage, and after that retrograde.
Look at the stats: 2 shock comas(24% of life healed each turn) times 1.5 times 1.5 times 1.5 equals 81% healed each turn. Plus overdrive which doubles the damage/healing so 162% healed each turn.
now use retrograde and the enemy falls! XD