(Generic)Isekai/Dungeon Test concepts: Virtual Booster

Saproling Summoning Circle    R  Sorcery Search your library for a green creature with a mana value of X or less, where X is the number of creature tokens you control. Put that creature onto the battlefield.	Ancient Muck Elemental    U  Creature – Elemental Flash At the beginning of your end step, up to one target tapped nonlegendary creature an opponent controls gets -X/-X until end of turn, where C is the number of tapped creatures you control. 5/5	Cheline, Light Elf Gate Keeper    U  Legendary Creature – Elf Cleric Boss Vigilance Tier 2 (Tier 2 creatures aren't legendary as long as you control a Tier 3 or higher creature.) At the beginning of your endstep, gain 1 life for each untapped creature you control. At the beginning of your upkeep, if you have more life than each opponent, distribute up to two +1/+1 counters among one or two target creatures. 3/4	Nuvilee, Forge-Frenzied    U  Legendary Creature – Kor Artificer Boss Tier 2 (Tier 2 creatures aren't legendary as long as you control a Tier 3 or higher creature.) Whenever Nuvilee, Forge-Frenzied attacks, Nuvilee gets +X/+X until end of turn, where X is the number of artifacts that entered the battlefield under your control this turn. If X is 0 or less, create a tapped Treasure token instead. 3/1	Hollyhock Mount    C  Creature – Lizard Hollyhock Mount can't be blocked by creatures with a power of 2 or less. Hollyhock knights ride lizards, adept at running through the forests, climbing trees, and swimming through the lakes. 3/3
Adventurercatcher    C  Creature – Plant Whenever a land enters the battlefield under your control, gain 1 life. If a Lair entered the battlefield, Adventurercatcher gets +1/+0 until end of turn. 0/1	Fourth-Floor Ambush Greeter    C  Creature – Elemental Giant When Fourth-Floor Ambush Greeter enters the battlefield, you may sacrifice a Lair. If you do, put a +1/+1 counter, a menace counter, and a first strike counter on each Boss you control. 6/6	Preshayja, the Sword-Twirler    C  Legendary Creature – Human Knight Boss Doublestrike Tier 1 (Tier 1 creatures aren't legendary as long as you control a Tier 2 or higher creature.) Preshayja, the Sword-Twirler has vigilance as long as Preshayja is enchanted. "Inevitable, painful death lies ahead, or at least, the promise of it does for me."- Preshayja, first floor boss. 1/2	Reapers Guild Novice    C  Creature – Gorgon Assassin Flash When Reapers Guild Novice enters the battlefield, target creature an opponent controls gets -4/-4 until end of turn. 3/5	Pleya's Strike    C  Sorcery Until end of turn, target creature gains "Whenever this creature deals combat damage to a player, draw a card." The Murky Murderer's bites can draw more than just blood.
Olvaicz, Heaven Ruptured    C  Legendary Creature – Angel Boss Flying Tier 1 (Tier 1 creatures aren't legendary as long as you control a Tier 2 or higher creature.) When Olvaicz, Heaven Ruptured dies, destroy target nonland permanent with a mana value of three or less. 2/2	Dungeon Haunt    C  Creature – Spirit Flying, menace Whenever a creature you control dies, Dungeon Haunt gets +1/+0 until end of turn. 3/1	Dark Elf Blight Hexer    C  Creature – Elf Assassin Sacrifice an enchantment: Target creature gains deathtouch until end of turn. 1/2	Bubble Capture    C  Enchantment – Aura Enchant creature Tap enchanted creature. That creature doesn't untap during its controller's next untap step. At the beginning of your endstep, attach Bubble Capture to another creature controlled by the same player.	Swamp    B  Basic Land – Swamp

Saproling Summoning Circle (rare)
Ancient Muck Elemental (uncommon)
Cheline, Light Elf Gate Keeper (uncommon)
Nuvilee, Forge-Frenzied (uncommon)
Hollyhock Mount (common)
Adventurercatcher (common)
Fourth-Floor Ambush Greeter (common)
Preshayja, the Sword-Twirler (common)
Reapers Guild Novice (common)
Pleya's Strike (common)
Olvaicz, Heaven Ruptured (common)
Dungeon Haunt (common)
Dark Elf Blight Hexer (common)
Bubble Capture (common)
Swamp (basic)