Dakkaldure, the Sunken

Flying, prowess, islandwalk
When Dakkaldure, the Sunken deals combat damage to a player, draw up to X cards, then
discard that many cards, where X is equal to the number of Merfolk you control.
Shuffle three Merfolk you control into their owner's library: Return Dakkaldure from your graveyard or exile to the battlefield.