Hex

Haste Counters are not removed from Hex if it would be put into exile. Whenever you cast an Adventure spell, if Hex, Kellan’s Companion is on the battlefield put a +1/+1 counter on this creature. Then if it’s on the battlefield, exile it with a fetch counter on it. Whenever you cast a spell from exile, if Hex is in exile with a fetch counter on it, remove the fetch counter and put it onto the battlefield.