Bloomburrow

Plumecreed Mentor | Creature | Bird Scout | Flying Whenever Plumecreed Mentor or another creature you control with flying enters, put a +1/+1 counter on target creature you control without flying. | Henry Peters

Starseer Mentor | Creature | Bat Warlock | Flying, vigilance At the beginning of your end step, if you gained or lost life this turn, target opponent loses 3 life unless they sacrifice a nonland permanent or discard a card. | Taras Susak

Seedglaive Mentor | Creature | Mouse Soldier | Vigilance, haste Valiant — Whenever Seedglaive Mentor becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it. | Vincent Christiaens

Burrowguard Mentor | Creature | Rabbit Soldier | Trample Burrowguard Mentor's power and toughness are each equal to the number of creatures you control. | Dmitry Burmak

Tidecaller Mentor | Creature | Rat Wizard | Menace Threshold — When Tidecaller Mentor enters, if seven or more cards are in your graveyard, return up to one target nonland permanent to its owner's hand. | Irina Nordsol

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

Lilysplash Mentor | Creature | Frog Druid | Reach {1}{G}{U}: Exile another target creature you control, then return it to the battlefield under its owner's control with a +1/+1 counter on it. Activate only as a sorcery. | Aldo Domínguez

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

Vinereap Mentor | Creature | Squirrel Druid | When Vinereap Mentor enters or dies, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.") | Valera Lutfullina

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