At the beginning of combat on your turn, up to one target land you control becomes an X/X Elemental creature with trample and haste until end of turn, where X is Obuun's power. It's still a land.
Landfall — Whenever a land enters the battlefield under your control, put a +1/+1 counter on target creature.

[+1]: Put two +1/+1 counters on up to one target creature you control.
[0]: Until end of turn, Oko, the Trickster becomes a copy of target creature you control. Prevent all damage that would be dealt to him this turn.
[−7]: Until end of turn, each creature you control has base power and toughness 10/10 and gains trample.

Discard a card: Olivia's Dragoon gains flying until end of turn.

Draft Paliano Vanguard face up.
As you draft a creature card, you may reveal it, note its creature types, then turn Paliano Vanguard face down.
Other creatures you control of a type you noted for cards named Paliano Vanguard get +1/+1.

Put a +1/+1 counter on each creature you control. You gain 1 life for each creature you control.

Draw three cards.
Addendum — If you cast this spell during your main phase, instead scry 3, then draw three cards.

Flying
Tap another untapped creature you control with flying: Radiant, Serra Archangel gains protection from the color of your choice until end of turn.
Partner (You can have two commanders if they both have partner)

Flying, trample
Pay 2 life, Sacrifice another creature: Search your library for a card and put that card into your hand. Then shuffle your library.

Devoid (This card has no color.)
Reality Hemorrhage deals 2 damage to any target.

Devoid (This card has no color.)
At the beginning of your upkeep, you lose 1 life unless you control another colorless creature.

Redcap Melee deals 4 damage to target creature or planeswalker. If a nonred permanent is dealt damage this way, you sacrifice a land.

Reveal Regicide as you draft it. The player to your right chooses a color, you choose another color, then the player to your left chooses a third color.
Destroy target creature that's one or more of the colors chosen as you drafted cards named Regicide.

Choose one —
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.

Reyhan, Last of the Abzan enters the battlefield with three +1/+1 counters on it.
Whenever a creature you control dies or is put into the command zone, if it had one or more +1/+1 counters on it, you may put that many +1/+1 counters on target creature.
Partner (You can have two commanders if both have partner.)

Rimrock Knight can't block.

Target creature gets +2/+1 and gains trample until end of turn.

Flying, lifelink
Megamorph (You may cast this card face down as a 2/2 creature for . Turn it face up any time for its megamorph cost and put a +1/+1 counter on it.)
When Shieldhide Dragon is turned face up, put a +1/+1 counter on each other Dragon creature you control.

Support 2. (Put a +1/+1 counter on each of up to two target creatures.)
Draw a card.

When Siona, Captain of the Pyleas enters the battlefield, look at the top seven cards of your library. You may reveal an Aura card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Whenever an Aura you control becomes attached to a creature you control, create a 1/1 white Human Soldier creature token.

Flying
When Siren Lookout enters the battlefield, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)