In terms of gameplay, Karns one colorless mana activated ability can be quite useful if youre looking to turn your mana rocks into attackers out of nowhere, but this cards value is tied more to its rarity and Karns lore significance
Shantotto, Tactician Magician A limited focused card for the UR cast big spells archetype which seems like a perfectly decent little dude, who also loves affinity for artifacts
If you're in a position where taking two extra turns and casting a ten mana spell is something you can do, odds are you don't even need the extra turn at all, and can win with whatever you're already working with
Take out the cost-cheating cards like Aetherplasm and Belbe's Portal, and then maybe consider shaving off stuff like Cabal Coffers, Crypt Ghast, and Bubbling Muck until your deck is at the speed that you're aiming for
Its no secret that some MTG players hate to play against land destruction and that MTG developers dont incentivize this play pattern anymore
The Thundertrap Wizard gets ready to cast a spell, whispering to voices only he can hear