Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Sol Ring

Awaken the Blood Avatar

As an additional cost to cast this spell, you may sacrifice any number of creatures. This spell costs {2} less to cast for each creature sacrificed this way.
Each opponent sacrifices a creature of their choice. Create a 3/6 black and red Avatar creature token with haste and "Whenever this token attacks, it deals 3 damage to each opponent."

Extus, Oriq Overlord

Double strike
Magecraft — Whenever you cast or copy an instant or sorcery spell, return target nonlegendary creature card from your graveyard to your hand.

Extus, Oriq Overlord // Awaken the Blood Avatar

Mayhem Devil

Whenever a player sacrifices a permanent, this creature deals 1 damage to any target.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Nomad Outpost

This land enters tapped.
{T}: Add {R}, {W}, or {B}.

Mahadi, Emporium Master

At the beginning of your end step, create a Treasure token for each creature that died this turn. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Flamekin Herald

Commander spells you cast have cascade. (Whenever you cast a commander, exile cards from the top of your library until you exile a nonland card with lesser mana value. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)