Siren's Call Visions Cast it as a sorcery

Cast it as a sorcery on a later turn without paying its mana cost

{T}: Gain control of target creature with power less than or equal to this creature's power for as long as this creature remains tapped and that creature's power remains less than or equal to this creature's power

Whenever one or more +1/+1 counters are put on this creature

create two 2/2 black Zombie creature tokens

+ {1} — Creatures you control with power 4 or greater gain hexproof and indestructible until end of turn

Siren's Call Visions Cast it as a sorceryCast this spell only during an opponent's turn, before attackers are declared. Creatures the active player controls attack this turn if able. At the beginning of the next end step, destroy all non Wall creatures that player controls that didn't attack this turn. Ignore this effect for each creature the player didn't control continuously since the beginning of the turn.