Spitemare

Whenever this creature is dealt damage, it deals that much damage to any target.

Boros Reckoner

Whenever this creature is dealt damage, it deals that much damage to any target.
{R/W}: This creature gains first strike until end of turn.

Deflecting Palm

The next time a source of your choice would deal damage to you this turn, prevent that damage. If damage is prevented this way, Deflecting Palm deals that much damage to that source's controller.

Mountain

Always Watching

Nontoken creatures you control get +1/+1 and have vigilance.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Mirror Strike

All combat damage that would be dealt to you this turn by target unblocked creature is dealt to its controller instead.

Plains

Gideon's Sacrifice

Choose a creature or planeswalker you control. All damage that would be dealt this turn to you and permanents you control is dealt to the chosen permanent instead (if it's still on the battlefield).

Spiteful Sliver

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

Reflect Damage

The next time a source of your choice would deal damage this turn, that damage is dealt to that source's controller instead.

Eye for an Eye

The next time a source of your choice would deal damage to you this turn, instead that source deals that much damage to you and Eye for an Eye deals that much damage to that source's controller.