Guilds of Ravnica

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

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

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

Goblin Electromancer | Creature | Goblin Wizard | Instant and sorcery spells you cast cost {1} less to cast. | Svetlin Velinov

Hypothesizzle | Instant | | Draw two cards. Then you may discard a nonland card. When you do, Hypothesizzle deals 4 damage to target creature. | Chris Seaman

Sonic Assault | Instant | | Tap target creature. Sonic Assault deals 2 damage to that creature's controller. Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.) | Tyler Walpole

Piston-Fist Cyclops | Creature | Cyclops | Defender As long as you've cast an instant or sorcery spell this turn, Piston-Fist Cyclops can attack as though it didn't have defender. | Wayne Reynolds