Hungering Hydra enters the battlefield with X +1/+1 counters on it. Hungering Hydra can't be blocked by more than one creature. Whenever Hungering Hydra is dealt damage, put that many +1/+1 counters on it. (It must survive the damage to get the counters.)

When you cast this spell, you gain half X life and draw half X cards. Round down each time. Flying, trample Hydroid Krasis enters the battlefield with X +1/+1 counters on it.

Temple of Mystery enters the battlefield tapped. When Temple of Mystery enters the battlefield, scry 1. {T}: Add {G} or {U}.

Whenever Risen Reef or another Elemental enters the battlefield under your control, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped. If you don't put the card onto the battlefield, put it into your hand.

Trample Voracious Hydra enters the battlefield with X +1/+1 counters on it. When Voracious Hydra enters the battlefield, choose one — • Double the number of +1/+1 counters on Voracious Hydra. • Voracious Hydra fights target creature you don't control.