Guilds of Ravnica

Dimir Informant | Creature | Human Rogue | When Dimir Informant enters the battlefield, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.) | Lucas Graciano

Leapfrog | Creature | Frog | Leapfrog has flying as long as you've cast an instant or sorcery spell this turn. | Aaron Miller

Darkblade Agent | Creature | Human Assassin | As long as you've surveilled this turn, Darkblade Agent has deathtouch and "Whenever this creature deals combat damage to a player, you draw a card." | Joe Slucher

Thief of Sanity | Creature | Specter | Flying Whenever Thief of Sanity deals combat damage to a player, look at the top three cards of that player's library, exile one of them face down, then put the rest into their graveyard. You may look at and cast that card for as long as it remains exiled, and you may spend mana as though it were mana of any type to cast that spell. | Igor Kieryluk

Whisper Agent | Creature | Human Rogue | Flash When Whisper Agent enters the battlefield, surveil 1. (Look at the top card of your library. You may put it into your graveyard.) | Deruchenko Alexander

Wee Dragonauts | Creature | Faerie Wizard | Flying Whenever you cast an instant or sorcery spell, Wee Dragonauts gets +2/+0 until end of turn. | Greg Staples

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