Guilds of Ravnica

Legion Warboss | Creature | Goblin Soldier | 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, create a 1/1 red Goblin creature token. That token gains haste until end of turn and attacks this combat if able. | Alex Konstad

Risk Factor | Instant | | Target opponent may have Risk Factor deal 4 damage to them. If that player doesn't, you draw three cards. 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.) | Chris Seaman

Deafening Clarion | Sorcery | | Choose one or both — • Deafening Clarion deals 3 damage to each creature. • Creatures you control gain lifelink until end of turn. | Adam Paquette

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

Ionize | Instant | | Counter target spell. Ionize deals 2 damage to that spell's controller. | Chase Stone