There are other options for loops like this, the best ones being Glen-Elendra Archmage, River Kelpie, and Geralf's Mindcrusher, but each requires a free Land sac outlet (e.g
Whenever you cast a Myr spell, Urtet gives you another Myr and all your Myr untap at the beginning of your combat step
This means that when making a discard spell, always make it a sorcery unless it can only function as an instant
Contaminant Grafter Provides poison counters, proliferates, and draws cards when an opponent is corrupted
One note: because the cards have not yet been put into Gatherer, our card database, new cards will not show up as something you can hover over and they will all be grouped under "Other" instead of "Creature" or "Land" or the like
If there is a keyword or an ability word or even a word used in the title of multiple cards using this ability, then we (being Wizards) have done our job to help name this ability