mtg fabricate cards Instant Deck Tech: WB (Standard) then shuffle. 📚Fabricate📚 “The secret to invention

This allows you to put your choice of a +1/+1 counter or two charge counters on up to one other target artifact, at the beginning of combat on your turn

And it does explain why the information I was looking for is hard to find

Once it has 3 or more charge counters, it starts drawing you a card and gaining a charge counter for every Artifact spell you cast, and this deck has plenty of those

The value of X is determined only once, as Proft's Eidetic Memory's last ability resolves

4 Invigorating Hot Spring Grants Haste Through +1/+1 Counters Invigorating Hot Spring is green in addition to red, but it's also an uncommon signpost that can make for a very good green/red modified creature build