Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Lumbering Battlement

Vigilance
When Lumbering Battlement enters, exile any number of other nontoken creatures you control until it leaves the battlefield.
Lumbering Battlement gets +2/+2 for each card exiled with it.

Corpse Knight

Whenever another creature you control enters, each opponent loses 1 life.

Cloudshift

Exile target creature you control, then return that card to the battlefield under your control.