Rocco, Street Chef

At the beginning of your end step, each player exiles the top card of their library. Until your next end step, each player may play the card they exiled this way.
Whenever a player plays a land from exile or casts a spell from exile, you put a +1/+1 counter on target creature and create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Arcane Signet

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

Victory Chimes

Untap Victory Chimes during each other player's untap step.
{T}: A player of your choice adds {C}.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Sol Ring

Selesnya Signet

Boros Signet

Gruul Signet

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.