Guilds of Ravnica

Aurelia, Exemplar of Justice | Legendary Creature | Angel | Flying Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) At the beginning of combat on your turn, choose up to one target creature you control. Until end of turn, that creature gets +2/+0, gains trample if it's red, and gains vigilance if it's white. | Chris Rahn

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

Garrison Sergeant | Creature | Viashino Soldier | Garrison Sergeant has double strike as long as you control a Gate. | Gabor Szikszai

Hammer Dropper | Creature | Giant Soldier | Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) | Lake Hurwitz

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

Skyknight Legionnaire | Creature | Human Knight | Flying, haste | Chase Stone

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

Swiftblade Vindicator | Creature | Human Soldier | Double strike, vigilance, trample | Viktor Titov

Tajic, Legion's Edge | Legendary Creature | Human Soldier | Haste Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.) Prevent all noncombat damage that would be dealt to other creatures you control. {R}{W}: Tajic, Legion's Edge gains first strike until end of turn. | Anthony Palumbo

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

Fresh-Faced Recruit | Creature | Human Soldier | As long as it's your turn, Fresh-Faced Recruit has first strike. | Anthony Palumbo

Chamber Sentry | Artifact Creature | Construct | Chamber Sentry enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it. {X}, {T}, Remove X +1/+1 counters from Chamber Sentry: It deals X damage to any target. {W}{U}{B}{R}{G}: Return Chamber Sentry from your graveyard to your hand. | Adam Paquette