Bloomburrow

Blooming Blast | Instant | | Gift a Treasure (You may promise an opponent a gift as you cast this spell. If you do, they create a Treasure token before its other effects. It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.") Blooming Blast deals 2 damage to target creature. If the gift was promised, Blooming Blast also deals 3 damage to that creature's controller. | Jakob Eirich

Brazen Collector | Creature | Raccoon Rogue | First strike Whenever Brazen Collector attacks, add {R}. Until end of turn, you don't lose this mana as steps and phases end. | Aldo Domínguez

Coruscation Mage | Creature | Otter Wizard | Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.) Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent. | Gaboleps

Flamecache Gecko | Creature | Lizard Warlock | When Flamecache Gecko enters, if an opponent lost life this turn, add {B}{R}. {1}{R}, Discard a card: Draw a card. | Brian Valeza

Hoarder's Overflow | Enchantment | | When Hoarder's Overflow enters and whenever you expend 4, put a stash counter on it. (You expend 4 as you spend your fourth total mana to cast spells during a turn.) {1}{R}, Sacrifice Hoarder's Overflow: Discard your hand, then draw cards equal to the number of stash counters on Hoarder's Overflow. | Andrea Radeck

Playful Shove | Sorcery | | Playful Shove deals 1 damage to any target. Draw a card. | Zoltan Boros

Rabid Gnaw | Instant | | Target creature you control gets +1/+0 until end of turn. Then it deals damage equal to its power to target creature you don't control. | Mark Behm

Stormcatch Mentor | Creature | Otter Wizard | Haste Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.) Instant and sorcery spells you cast cost {1} less to cast. | Manuel Castañón

Fireglass Mentor | Creature | Lizard Warlock | At the beginning of your second main phase, if an opponent lost life this turn, exile the top two cards of your library. Choose one of them. Until end of turn, you may play that card. | Henry Peters

Wandertale Mentor | Creature | Raccoon Bard | Whenever you expend 4, put a +1/+1 counter on Wandertale Mentor. (You expend 4 as you spend your fourth total mana to cast spells during a turn.) {T}: Add {R} or {G}. | Jakub Kasper