[LockDown]

Just for clarification:

Originally Posted by Fat DAT

Substitute: The Pokemon siphons 15, 20, or 25 HP of its life force and creates a Substitute. The Substitute can absorb damage and status attacks for the user. When Substitute is constructed, status effects and secondary effects cannot be inflicted. Taunt and Torment ignore this, however. Substitute will block all stat-lowering attacks and other new effects except for Attract, Curse, Destiny Bond, Encore, Grudge, Perish Song, Psych Up, Roar, Taunt and Whirlwind. While a Substitute is up, an opposing Pokemon will not take recoil damage from an attack with recoil, or take damage from Life Orb recoil.

Does Giga Drain's draining quality count as a secondary effect? (I'm not sure about in the games)
Anyway, "Continue attacking, Zubat!"

Giga Drain > Air Cutter > Giga Drain
If Damaging Evasive action when Buneary doesn't have a Substitute, use Steel Wing Attack (Steel Wing + Wing Attack) that turn instead