Sol Ring

Blazing Archon

Arcane Signet

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

Agatha of the Vile Cauldron

Activated abilities of creatures you control cost {X} less to activate, where X is Agatha's power. This effect can't reduce the mana in that cost to less than one mana.
{4}{R}{G}: Other creatures you control get +1/+1 and gain trample and haste until end of turn.

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.

Serra's Emissary

Flying
As this creature enters, choose a card type.
You and creatures you control have protection from the chosen card type.