Carmen, Cruel Skymarcher

Flying
Whenever a player sacrifices a permanent, put a +1/+1 counter on Carmen, Cruel Skymarcher and you gain 1 life.
Whenever Carmen attacks, return up to one target permanent card with mana value less than or equal to Carmen's power from your graveyard to the battlefield.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Unstable Obelisk

{T}: Add {C}.
{7}, {T}, Sacrifice Unstable Obelisk: Destroy target permanent.

Orzhov Signet

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Sol Ring

Arcane Signet

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