Dimir Signet

Mountain

Izzet Signet

Swamp

Island

Arcane Signet

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

Sol Ring

Rakdos Signet

Evelyn, the Covetous

Flash
Whenever Evelyn or another Vampire you control enters, exile the top card of each player's library with a collection counter on it.
Once each turn, you may play a card from exile with a collection counter on it if it was exiled by an ability you controlled, and you may spend mana as though it were mana of any color to cast it.

Fellwar Stone

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

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, this artifact deals 3 damage to you.
{T}: Add {C}{C}.