Arcane Signet

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

Plains

Mountain

Fyndhorn Elves

Elvish Mystic

Selvala, Heart of the Wilds

Whenever another creature enters, its controller may draw a card if its power is greater than each other creature's power.
{G}, {T}: Add X mana in any combination of colors, where X is the greatest power among creatures you control.

Mayael the Anima

{3}{R}{G}{W}, {T}: Look at the top five cards of your library. You may put a creature card with power 5 or greater from among them onto the battlefield. Put the rest on the bottom of your library in any order.