I have two questions.

1st ouestion:
How do I berserk an enemy?

2nd question:
[spoilers maybe] I'm trying to use coin toss on X-Death and NeoX-Deth but the damage is only like 1200 HP damage. Doesn't do like 4000 damage. What's wrong?

1st answer: Cast 'Berserk' on your enemy.

2nd answer: You're running short of Gil.

How do I get berserk?

You buy it. It's white magic.

Yeah, just be careful, I remember beserk being called 'bersk'. Try using that.