If you have access to blue in your deck, you can use Machine God's Effigy to become a copy of Devoted Druid, except its still an artifact, letting you jam as many -1/-1 counters on it as possible with no threat of it dying
If an activated ability of a creature you control costs no generic mana to activate (for example, if it costs , it costs, or it costs only nonmana actions such asor "Sacrifice a creature"), Training Grounds simply won't affect it
While it never required a banning, the overall trajectory of Teferi, Temporal Archmage reminds me a lot of the general sentiment around Leovold, Emissary of Trest: fun and powerful, but once most players had done the most powerful thing they could think of with Teferi, interest waned
Well be updating our Lorcana card database as soon as we get a second to breathe
At best, you're getting an Ancestral Recall on a 6/6 with first strike