Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.

Wormhole Serpent

{3}{U}: Target creature can't be blocked this turn.

Kiora, Behemoth Beckoner

Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.
−1: Untap target permanent.

Fleet Swallower

Whenever Fleet Swallower attacks, target player mills half their library, rounded up.

Sailors' Bane

This spell costs {1} less to cast for each card you own in exile and in your graveyard that's an instant card, a sorcery card, or a card that has an Adventure.
Ward {4} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {4}.)