Jyoti, Moag Ancient

When Jyoti, Moag Ancient enters, create a 1/1 green Forest Dryad land creature token for each time you've cast your commander from the command zone this game. (They're affected by summoning sickness.)
At the beginning of each combat, land creatures you control get +X/+X until end of turn, where X is Jyoti's power.

Scan the Clouds

Draw two cards, then discard two cards. (Then exile this card. You may cast the creature later from exile.)

Tempest Hart

Trample
Whenever you cast a spell with mana value 5 or greater, put a +1/+1 counter on Tempest Hart.

Tempest Hart // Scan the Clouds

Sturdy Hatchling

Sturdy Hatchling enters with four -1/-1 counters on it.
{G/U}: Sturdy Hatchling gains shroud until end of turn. (It can't be the target of spells or abilities.)
Whenever you cast a green spell, remove a -1/-1 counter from Sturdy Hatchling.
Whenever you cast a blue spell, remove a -1/-1 counter from Sturdy Hatchling.

Wavesifter

Flying
When Wavesifter enters, investigate twice. (To investigate, create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")
Evoke {G}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Parcelbeast

Mutate {G}{U} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
{1}, {T}: Look at the top card of your library. If it's a land card, you may put it onto the battlefield. If you don't put the card onto the battlefield, put it into your hand.

Risen Reef

Whenever Risen Reef or another Elemental you control enters, 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.