Here's a guide, but for a written guide:
1. Go to the far left side of Valeshire after unlocking the ability to smash bricks in a boss battle.
2. Go into the house behind the bricks.
3. Talk to the lady, agree to handle the problem in her basement.
4. Fight the mini-boss. Beating it will unlock the ability.
- He has three attacks: Falling ceiling, big fire ball, small barrage of fire balls.
- Hit the small and big fire balls back at the exposed eyeball.
- One is high, one is low. So his the attack back either low or high, accordingly.
- Be patient, and continue to dodge the falling ceiling/fire balls.