Arlen-Nea, Mind Breaker

Whenever Arlen-Nea, Mind Breaker enters the
battlefield, gain control of target creature until
your next turn. Untap that creature, it gains
haste until end of turn.
Whenever one or more Hydra creatures you
control deal combat damage to an opponent,
goad target creature that player controls.
Whenever a Hydra you control dies each
opponent discards a random card.