Alter Reality, Artificial Evolution, and Magical Hack are examples that target spells on the stack
be on the lookout, too, because lots of cards that see Commander play naturally sacrifice themselvesfetchlands, [mtg_card]Evolving Wilds[/mtg_card], and [mtg_card]Burnished Hart[/mtg_card] are some to watch for
Kappa Cannoneer is a threat that scales fast, too, with each artifact played adding a +1/+1 counter to the creature and making it unblockable
Black Rob Lucci is a control deck that relies on 4-cost Rob Lucci as its main removal option
There are some really impactful commanders in Strixhaven that will shake up the market, as well as some cool new planeswalkers
One mana for two +1/+1 counters is a great deal and helps you stay ahead of the mana curve on power and toughness