Guilds of Ravnica

Boros Challenger | Creature | Human Soldier | Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) {2}{R}{W}: Boros Challenger gets +1/+1 until end of turn. | Gabor Szikszai

Justice Strike | Instant | | Target creature deals damage to itself equal to its power. | Clint Cearley

Legion Guildmage | Creature | Human Wizard | {5}{R}, {T}: Legion Guildmage deals 3 damage to each opponent. {2}{W}, {T}: Tap another target creature. | Zack Stella

Swathcutter Giant | Creature | Giant Soldier | Vigilance Whenever Swathcutter Giant attacks, it deals 1 damage to each creature defending player controls. | Aaron Miller

Truefire Captain | Creature | Human Knight | Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) Whenever Truefire Captain is dealt damage, it deals that much damage to target player. | Chris Rallis

Integrity | Instant | | Target creature gets +2/+2 until end of turn. | Ben Maier