Embrace of the Tistina (AGOV-EN091) [Age of Overlord]

When your opponent activates a monster effect on the field: You can target that monster; change it to face-down Defense Position. During the End Phase: You can target 1 face-down Defense Position monster your opponent controls; take control of that monster. You can only use each effect of "Embrace of the Tistina" once per turn, and can only activate them while you control a "Tistina" monster with 3000 or more DEF.