Capricopian

   Creature — Goat Hydra

Capricopian enters the battlefield with X +1/+1 counters on it.
; Put a +1/+1 counter on Capricopian, then you may reselect which player Capricopian is attacking. Only the player Capricopian is attacking may activate this ability and only during the declare attackers step. (It can't attack its controller.)

Illustrated by Nicholas Gregory