Denizen of the Deep

Emerge (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)

When this creature enters, if you cast it, return each non-Dinosaur creature to its owner's hand.

Assist (Another player can pay up to of this spell's cost.)

When this creature enters, you may return target tapped creature to its owner's hand.

When this creature enters, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Flying

When this creature enters, untap up to seven lands.

: Return this creature to its owner's hand.

When this creature enters, return all other nonland permanents to their owners' hands.

Unearth (: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Flying

When this creature enters, you may return up to two target creatures to their owners' hands.