I love this idea, which feels like a twist and refinement on the Bloomburrow Expend Mechanic (except you've got to pay it all on one spell), and anything that sweetens the pot when it comes to casting big instant and sorcery spells sounds good to me
These rare cards' availability will be based on Tolkien's iconic poem detailing how many of each kind of ring were made
However, you get a poison counter on your every upkeep that it stays on the field
The land requirements to pull together a solid four-color deck are a pretty big step up from three colors, and your colored spells can be easier to cast on time for a three-color deck
Feel free to let us know the biggest, most glaring, misses down below in the comments or in the official Draftsim Discord
It's a win condition that converts all those cheap spells into an onboard advantage, and Murktide only gets bigger as the game continues