Each player loses a third of their life, then discards a third of the cards in their hand, then sacrifices a third of the creatures they control of their choice, then sacrifices a third of the lands they control of their choice. Round up each time.

Create thirteen tapped 2/2 black Zombie creature tokens.
Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Trample, haste
Whenever Eivor deals combat damage to a player, you mill that many cards. You may put a Saga card and/or a land card from among them onto the battlefield.

Flying (This creature can't be blocked except by creatures with flying or reach.)
: Return this creature to its owner's hand.

Offspring (You may pay an additional as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
When this creature enters, look at the top four cards of your library. You may reveal a noncreature, nonland card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

+1: Create a 3/3 Kavu creature token with trample that's all colors.
−3: Choose up to two target creatures. For each of them, put a number of +1/+1 counters on it equal to the number of colors it is.
−6: Return target multicolored card from your graveyard to your hand. If that card was all colors, draw a card and create two Treasure tokens.
Jared Carthalion can be your commander.

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)

Unreliable Visions — At the beginning of your first main phase, discard a card. If you do, draw a card.
Undying Vengeance — Whenever you play a land or cast a spell from anywhere other than your hand, this enchantment deals 1 damage to each opponent.

Target opponent sacrifices a creature of their choice.

First strike
Other creatures you control have haste.
Whenever Smellerbee attacks, you may discard your hand. If you do, draw cards equal to the number of attacking creatures.

Whenever this creature attacks, target player mills half their library, rounded up.

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for .)
Bottle-Cap Blast deals 5 damage to any target. If excess damage was dealt to a permanent this way, create that many tapped Treasure tokens. (They're artifacts with ", Sacrifice this token: Add one mana of any color.")

Flying
Creature spells with flying you cast cost less to cast.

, Pay 1 life: Counter target white spell.

( can be paid with either or .)
Other green creatures you control get +1/+1.
Other white creatures you control get +1/+1.
If a spell or ability an opponent controls causes you to discard this card, put it onto the battlefield instead of putting it into your graveyard.

Enchant land
Enchanted land has shroud. (It can't be the target of spells or abilities.)
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

(: Add .)

Flying
: Tap all creatures target player controls.

Flash
Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When this creature exploits a creature, counter target spell, activated ability, or triggered ability.

Haste
Whenever one or more other attacking legendary creatures you control die, untap all creatures you control. After this phase, there is an additional combat phase. This ability triggers only once each turn.