When Ajani's Aid enters the battlefield, you may search your library and/or graveyard for a card named Ajani, Valiant Protector, reveal it, and put it into your hand. If you search your library this way, shuffle it.
Sacrifice Ajani's Aid: Prevent all combat damage a creature of your choice would deal this turn.
You can activate the last ability even if there is no creature about to deal combat damage, or even no creature at all. No damage will be prevented, but it will enable your revolt abilities.
The last ability of Ajaniâ€™s Aid doesnâ€™t target anything. You choose a source of damage as the ability resolves.