Hive Mind — Whenever a player mills one or more creature cards, you create a 1/1 black Horror creature token.
, : Target player mills three cards.
Choose a Background (You can have a Background as a second commander.)

Sacrifice any number of creatures. Last-Ditch Effort deals that much damage to any target.

Enchant creature card in a graveyard
When this Aura enters, if it's on the battlefield, it loses "enchant creature card in a graveyard" and gains "enchant creature put onto the battlefield with this Aura." Return enchanted creature card to the battlefield under your control and attach this Aura to it. When this Aura leaves the battlefield, that creature's controller sacrifices it.
Enchanted creature gets -1/-0.

Flash
When this creature enters, target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost. (You may cast that card from your graveyard for its flashback cost. Then exile it.)

: Add .
, Sacrifice this land: Destroy target land.

Whenever one or more creatures attack, this enchantment deals damage to each of those creatures equal to the number of attacking creatures.

+2: Create two 0/1 black Thrull creature tokens.
+1: You may sacrifice another creature or planeswalker. If you do, draw two cards, then draw another card if the sacrificed permanent was a commander.
−10: Gain control of all commanders. Put all commanders from the command zone onto the battlefield under your control.
Tevesh Szat, Doom of Fools can be your commander.
Partner

Cast this spell only during the declare attackers step and only if you've been attacked this step.
Prevent all damage that would be dealt to you this turn by attacking creatures.

Haste
When this creature enters, creatures you control gain trample and get +X/+0 until end of turn, where X is the number of artifacts you control.

Counter target spell.

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of your end step, exile up to one other target creature you control, then return that card to the battlefield under your control.
: Tap another target creature.

Target opponent puts the cards from their hand on top of their library. Search that player's library for that many cards. The player puts those cards into their hand, then shuffles.

Deathtouch
When God-Eternal Rhonas enters, double the power of each other creature you control until end of turn. Those creatures gain vigilance until end of turn.
When God-Eternal Rhonas dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

This spell can't be countered.
: Target spell can't be countered.

, Sacrifice this artifact: Exile target player's graveyard.

, Exile two cards from your graveyard: Create a 2/2 green Bear creature token.

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

You may cast Aura and Equipment spells as though they had flash.
Whenever an Equipment you control enters, you may attach it to target creature you control.

This land enters tapped unless you have two or more opponents.
: Add or .

Flying, trample
Whenever one or more opponents each lose exactly 1 life, put a +1/+1 counter on Ob Nixilis. Exile the top card of your library. Until your next end step, you may play that card.