Brooding Nerithrax

Creature - Dragon Serpent

Flying

Ward -

Whenever you are attacked by one or more creatures, choose one of them. At the end of combat, return that creature to its owners hand.

3/5

Create a piece of equipment (doesn't have to be a literal equipment) used to hunt nerithrax

Gorging Lur'Slug

Enchantment Creature - Slug Horror (Colour indicator: )

Bestow , Exile three other cards from your graveyard

You may activate Gorging Lur'Slug's Bestow ability from the graveyard.

Enchanted creature gets -2/-2 and has "Sacrifice this creature: Create a Blood token".

At the beginning of your upkeep end step, put a growth counter onto Gorging Lur'Slug.

When Gorging Lur'Slug or enchanted creature leaves the battlefield, create a number of 1/1 black Slug creatures and put a number of counters onto Gorging Lur'Slug equal to the number of growth counters on it.

0/1

Create a card that uses bestow in an unconventional way.

Mike Wazowski, Scare Assistant

Legendary Creature - Cyclops Horror

Partner with Sully, Top Scarer

At the beggining of your endstep, if you control the creature with the greatest power, draw a card and create a treasure token. If the next highest power on the battlefield is half or less than the first, instead create 3 treasure tokens and draw a card.

1/4

Sully, Top Scarer

Legendary Creature - Beast Horror

Trample

Partner with Mike Wazowski, Scare Assistant

Whenever Sully, Top Scarer attacks, double its power until end of turn.

: Sully gets +1/+1 until end of turn.

5/5

Make another monsters inc character, feel free to redo mike and/or sully if you have a different idea to what I've done.

Whorl-Witness Scarecrow

Artifact Creature - Scarecrow

Menace

Delirium - , Sacrifice Whorl-Witness Scarecrow: For up to four different card types, return a card of that type from your graveyard to your hand.

2/1

Create a card that has the text "A deck can have any number of cards named ~"

Bloated Scion

Creature - Eldrazi Scion

Devoid (This card has no colour)

When Bloated Scion leaves the battlefield, create a 1/1 colourless Eldrazi Scion creature token with "Sacrifice this creature: add to your mana pool"

Sacrifice Bloated Scion: add to your mana pool

2/2

As far as I'm aware there are no existing scions that aren't tokens.

The other creature type I was considering was Flagbearer, create a creature with that type.

Is Glint-Sleeve Siphoner worth considering?

Fortitudus, Avatar of Augmentation

Legendary Artifact Creature - God

~ costs less for each counter you have placed on permanents and players this turn.

At the beginning of your upkeep, you may remove all counters from a permanent or player. If you do, put twice that many counters of each type removed on another target permanent or player.

, Discard ~: Proliferate.

2/10

Create a card that flips coins or rolls dice

Bathe in Blood

Sorcery

If a creature died under you or a teammates control this turn, draw 2 cards and lose 2 life.

Then if 3 or more creatures under you or a teammates control died this turn, create 3 Blood tokens.

Then if 5 or more creatures under you or a teammates control died this turn, each opponent sacrifices three creatures.

Then if 13 or more creatures under you or a teammates control died this turn, each opponent loses 20 life and you and your teammates gain 20 life.

Fiery Gambit has always appealed to me design wise as a fairly cheap sorcery that can do something regular, but has inbuilt potential to go crazy and win the game if you push it.

Make another card that is impacted by what your teammate is doing.