Phoebe, Mind-Slaver Maltese

Whenever Phoebe, Mind-Slaver Maltese deals combat damage to a player, they mill two cards and you get {e}{e}(two energy counters).

Pay {e}{e}: Choose target creature card in a graveyard. Exile it with a brain counter on it. Activate only as a sorcery.

Rex has all activated abilities of all cards in exile with brain counters on them.