Lightning Helix

Lightning Helix deals 3 damage to any target and you gain 3 life.

Gruul Signet

Sol Ring

Boros Signet

Rith, Liberated Primeval

Flying, ward {2}
Other Dragons you control have ward {2}.
At the beginning of your end step, if a creature or planeswalker an opponent controlled was dealt excess damage this turn, create a 4/4 red Dragon creature token with flying.

Balefire Dragon

Flying
Whenever Balefire Dragon deals combat damage to a player, it deals that much damage to each creature that player controls.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Forest

Arcane Signet

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