Rat Colony [Dominaria] Legendary Enchantment Delirium — Grim Flayer gets

Delirium — Grim Flayer gets +2/+2 as long as there are four or more card types among cards in your graveyard

Set: Dissension Type: Creature — Human Advisor Mutant Rarity: Rare Cost: {4}{U}{U} Graft 4 (This creature enters the battlefield with four +1/+1 counters on it

Set: Conspiracy Type: Creature — Giant Soldier Rarity: Uncommon Cost: {5}{W} Will of the council — When Council Guardian enters the battlefield

Set: Friday Night Magic 2002 Type: Instant Rarity: Rare Cost: {1}{U}{U} Counter target spell

but with understanding of all the old ones

Rat Colony [Dominaria] Legendary Enchantment Delirium — Grim Flayer getsSet: Dominaria Type: Creature Rat Rarity: Common Cost: {1}{B} Rat Colony gets +1 +0 for each other Rat you control. A deck can have any number of cards named Rat Colony. Wreckage from the Phyrexian Invasion provided the rats with a seemingly unlimited number of breeding grounds.