Trap is a spell type which is only used on instants. It was introduced in Zendikar, and also featured in Worldwake.
Traps may be cast as for their regular mana cost, but also have an alternative cost should specific events occur. Usually, traps have abilities that undo whatever has made their alternative cost possible; for instance, a Trap that was enabled by two lands entering the battlefield under an opponent's control would destroy two lands.
- Whiplash Trap
Instant - Trap
If an opponent had two or more creatures enter the battlefield under his or her control this turn, you may pay rather than pay Whiplash Trap’s mana cost.
Return two target creatures to their owner's hand.
The card Pitfall Trap was based on the artifact Pit Trap.