Ashnod's Altar

Jeweled Lotus

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

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 creature 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

Talisman of Conviction

{T}: Add {C}.
{T}: Add {R} or {W}. Talisman of Conviction deals 1 damage to you.