MTGNexus

For this game, you are given a card, and a rarity to move it to. Try to keep it within the confines of the set as well.
EG: Given the card "risen reef" and the rarity rare, I would make the card:
Risen Reef 1GU
Creature - Elemental
Whenever this or another elemental enters the battlefield, reveal the top card of your library. If it's a land card, put it onto the battlefield, and you gain 1 life. Otherwise, put it into your hand and put a +1/+1 counter on Risen Reef.
1/1

Next: Any uncommon walker from war of the spark, upshifted to rare.

Arlinn, Moonchild 2GG
Legendary Planeswalker - Arlinn
At the beginning of your end step, you may pay G. If you do, create a 2/2 green Wolf creature token.
+1: Up to one target Wolf or Werewolf gains vigilance until end of turn and assigns its combat damage this turn as though it weren't blocked.
-6: Until end of turn, Wolves and Werewolves you control gain "Whenever this creature attacks, it deals damage equal to its power to any target."
{[4]}

Next:
Blightsteel Colossus at common
Nicol Bolas, Dragon-God at uncommon
Mogg Fanatic at rare

Image of Bolas 1UBR
Planeswalker - Bolas
At the beginning of your upkeep, you may put a loyalty counter on another target bolas planeswalker you control.
-3: Draw a card. Each opponent discards a card unless they sacrifice a permanent.
7

Mogg Flamecaster 1r
Creature - Goblin
r, sacrifice a goblin: mogg fanatic deals 2 damage to any target.
1/1

Next: Questing Beast at rare
Murderous Rider at uncommon
Beanstalk Giant at Rare or mythic, your choice.

Leguminous Titan 4GG
Creature - Giant (M)
Trample
Creatures you control get +X/+X, where X is the number of lands you control.
Lands you control are 0/0 creatures that are still lands.
0/0
Grand Planting XGG
Instant - Adventure
Reveal the top X cards of your library. Put all lands revealed this way onto the battlefield, and the rest on the bottom of your library.

Next:
Bump in the Night at mythic
Time Warp at uncommon
Ornithopter at rare

Nightly Disturbance B
Sorcery (M)
Target opponent loses 3 life.
Whenever an opponent takes damage during your turn, you may pay 1r. If you do, return nightly disturbance from your graveyard to your hand at the beginning of the next end step.

Thopter swarm 0
Artifact Creature - Thopter (R)
Whenever you cast an artifact spell, you may pay 1. If you do, create a token that's a copy of this creature.
Flying
0/2

Next: Questing Beast at rare
Murderous Rider at uncommon
Creeping Trailblazer, or any other signpost uncommon from M20, at rare.

Dark Executioner 2BB
Creature - Zombie Knight
Deathtouch
Dark Executioner enters the battlefield with a +1/+1 counter on it if a creature an opponent controlled died this turn.
3/2
///
Die Weeping 2B
Sorcery - Adventure
Target opponent sacrifices a creature.

Next:
Soul Warden at mythic
Demonspine Whip at rare
Maelstrom Archangel at uncommon

Lash of Bones RB
Artifact- Equipment
: Lash of bones deals 1 damage to target creature you control.
Equipped creature gets +1/+0 for each damage sources you control have dealt this turn and has trample.
Equip 2
Grixis loves cruelty so much, it sometimes needs to inflict it on itself.

Next:
Questing Beast at rare
Creeping Trailblazer, or any other signpost uncommon from M20, at rare.
Soul Warden at mythic

Transcendent Sister 5W
Creature - Human Cleric
When ~ or another creature enters the battlefield, double your life total.
1/1

Next:
Gingerbread Cabin at rare
Bitterblossom at uncommon
Grizzly Bears at mythic

Castle Maedovfood
Land
Castle Maedovfood enters the battlefield tapped unless you control a forest
t: add g.
1gg, t: create a food token.
"Are we sure that's a real castle?" - Syr Faren
"It says it is, who are we to judge?" - Yorvo

Next: Take a draft signpost uncommon, eg creeping trailblazer and make it rare.

Skyknight Vanguard -->

Sunhome Warlord 3RW
Creature - Giant Soldier
Token creatures you control have protection from converted mana cost 3 or greater.
Whenever Sunhome Warlord attacks, for each other attacking creature, create a 1/1 white Soldier creature token that's tapped and attacking.
4/4

Next:
Soldevi Sage at rare
Goblin Rimerunner at rare
Armageddon at common

Rimeguide Goblin R
Snow Creature - Goblin Warrior
Rimeguide goblin gets +1/+0 and has haste as long as you control at least other 3 snow permanents.
ss: Rimeguide goblin deals 1 damage to target creature. That creature can't block this turn.
1/2

Next: A Theros demigod at rare

Tymaret, Favored by Death 1bb
Legendary Enchantment Creature — Demigod (R)
Tymaret's power and toughness are each equal to your devotion to black.
Xb: Exile up to X plus one target cards from graveyards. You gain 1 life for each creature card exiled this way and each opponent loses 1 life for each noncreature card exiled this way.
*/*

Next: an Apex predator from Ikoria at uncommon

Savai Slinker RWB
Creature - Dinosaur Cat
Mutate 1RWB
First strike, haste
Whenever this creature mutates, other creatures you control gain lifelink until end of turn.
2/2

Ketria Roarer GUR
Creature - Beast Elemental
Mutate 1GUR
Flying
Whenever this creature mutates, scry 3.
3/3

Indatha Digger WBG
Creature - Cat Nightmare
Mutate 1WBG
Deathtouch
Whenever this creature mutates, exile all the cards in target player's graveyard.
3/3

Raugrin Stormer URW
Creature - Elemental Dinosaur
Mutate 1URW
Flying, vigilance
Whenever this creature mutates, noncreature permanents you control gain indestructible and noncreature spells you cast can't be countered until the beginning of your next turn.
2/2

Zagoth Grinder BGU
Creature - Nightmare Beast
Mutate 1BGU
Trample
Whenever this creature mutates, choose target card in a graveyard. Its owner puts it on the top or bottom of their library.
3/4

Next:
Mogg Infestation at common
Grip of Chaos at uncommon
Crazed Goblin at rare

Overrun by Gremlins 1R
Enchantment — Curse (c)
Enchant player
At the beginning of enchanted player's end step, create two 1/1 red Gremlin creature tokens, if a creature that player controlled died this turn.

Grip of Indecision 2R
Enchantment (u)
Whenever a spell or ability is put onto the stack, if it has a single target, flip a coin. If it's heads, that spell's controller reselects another target. (Select from among all legal targets.)

Crazier Goblin R
Creature —- Goblin Noble (R)
All other creatures attack each turn if able.
1/1

Next
Takklemaggot at common
Chub Toad at rare
Ice Cauldron at uncommon

Gorged Toad 2G
Creature - Frog
Menace, trample
Whenever this creature becomes blocked, it gets +2/+1 for each creature blocking it.
1/3

Next: Risen Reef at rare
Ajani's Pridemate at rare
mothra, supersonic queen at uncommon

Ajani's Captain 1w
Creature - Cat Warrior Cleric
Lifelink
Whenever you gain life, put that many +1/+1 counters on ~.
2/2

Next:
- common Altered Ego
- uncommon Fiend Artisan
- rare Infernal Scarring

Swelling Shapetoad GU
Creature - Shapeshifter Frog
Swelling Shapetoad enters the battlefield with a +1/+1 counter on it if there's a creature with power 4 or greater on the battlefield and a +1/+1 counter on it if there's a creature with toughness 4 or greater on the battlefield.
GU: Return Swelling Shapetoad to its owner's hand. If you do, you gain 1 life.
2/2

Next:
Ancient Craving at common
Rune-Scarred Demon at uncommon
Footbottom Feast at rare

Goblinkind Gala 1BB
Sorcery
Clash with an opponent. If you win, return a creature card from your graveyard to the battlefield. If you lose, put any number of creature cards from your graveyard on top of your library, then draw a card.

Next:
blood artist at rare
Lovestruck Beast // Heart's Desire at uncommon
Jolrael, Mwonvuli Recluse at mythic rare.

Garenbrig Bearrider 2G
Creature - Human Knight
At the beginning of combat, if you control another 2/2 creature, Garenbrig Bearrider gets +2/+2 until end of turn.
2/2
///
New Steed 1G
Sorcery - Adventure
Put a +1/+1 counter on target creature. It gains trample and vigilance until end of turn.

Jolrael, Jungle Empress 2GG
Legendary Creature - Human Druid
Whenever Jolrael, Jungle Empress attacks, draw a card.
Whenever you draw a card, if you have seven or more cards in hand, create a 7/7 green Elemental creature token with trample.
2/2

Next:
Iname as One at common
Ranger's Guile at rare
Ukud Cobra at rare

Wrath of Nature G
Instant
Escalate G (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
Target creature gets +3/+3.
Target creature gains trample until end of turn.
Target creature gains hexproof until end of turn.
Target creature gains reach until end of turn.


Next:
Any leyline at Common.
Abuna's Chant at Uncommon
Abomination of Gudul at Rare or above.

Gudul swooper 5BGU
Creature - Horror
Delve
Flying
Whenever this creature attacks, you draw a card and defending player discards a card.
Morph 4BGU, delve

Next:
Blood Artist at rare
Ajani, the Greathearted at uncommon
Angrath, Captain of Chaos at rare

Ajani, Hero of Ravnica 3{G/W}{G/W}
Legendary Planeswalker - Ajani
Creatures you control have "T: You gain 1 life."
-2: Until end of turn, whenever you cast a creature or planeswalker spell, put a +1/+1 or loyalty counter on target creature or planeswalker.
{[5]}

Next:
Dark Depths at common
Icatian Crier at rare
Samurai of the Pale Curtain at rare

Hamato, master of the pale curtain WW
Legendary Creature - Human Samurai (Rare)
Bushido 2
If a card would be put into a graveyard from anywhere, exile it instead and you gain 1 life.
1/2

Next:
Blood Artist at rare
Almighty Brushwagg at mythic rare
Fires of invention at uncommon.

Fires of Industry 1R
Instant
You can't cast spells this turn. Add R for each land you control.
Mountaincycling 2

Next:
Sun Titan at uncommon
Goblin Snowman at mythic
Eldrazi Conscription at common

Solar Sentinal 4ww

Creature - Giant

Vigilance

Whenever Solar Sentinal attacks, you may return target card with converted mana cost 3 or less from your graveyard to your hand.
5/5

Grumgully, the Generous at Rare
Phytotitan at Common
Uro, Titan of Nature's Wrath at Uncommon