Unlike most other rituals, Infernal Plunge is a sorcery, which is likely one of the reasons many people pass on it
That makes this a 6/5 for 5 mana that reads 'when this enters the battlefield, draw a card.' Keeper of the Keys: [Monarch Card] That is a really good bonus for being the monarch
The full SIR tier adds another $800-900 combined, and the elevated Illustration Rare prices (Misty's Psyduck IR at $57, Lapras IR at $34) mean even the supposedly cheaper tier carries weight
If you sacrifice your whole board into this card, one removal spell will ruin your day and youll have wasted your mana on an inefficient removal spell that likely wont win the game
Commander Decks Edge of Eternities comes with two preconstructed Commander decks
Lastly, lets talk about the actual mechanics of the card