Those are mostly advices for shortening:
Line 12: "infight", how about "struggle", I'm not quite sure if it fits here, also the description kinda sounds unnatural, how about: "Increases the power at low HP" or "The Power increases at low HP" ?
Line 15: Does it fit in one line if you cut the "the"? --> Cuts foe's HP in half.
Line 16, 17: Leave the "pierces", it simply says it halfs the enemy's Def.
Line 19: Short "Can only be used" down to "Usable".
Line 21, 22: Short it to "1/3 (1/4) of the dealt damage recoils."
Line 24: Change to "Preemptive strike possible."
Line 25: Shortable to "Boosted if user has..."
Line 26: Paraphrase it to "Double power if allied puppet was defeated in prev. turn"
OK, this is how far I'll read. The translation is correct (until the point I have read), however often very costly expressed.
IDK, how much space we have, but I thought I could give few suggestions.
