mtg cards with squirrel art Magic The Gathering, Secret Lair: We Hope You Like Squirrels – Card Monster Games put a +1/+1 counter on target creature you control. What is the most powerful

Later on it is negligible

It was so dominant that people even played Jace Beleren, the cheaper 3-mana Jace, partly as a weird answer to it, because the planeswalker legend rule at the time let you drop your own Jace and immediately get rid of your opponents

Beyond just being powerful on its own, Insight Engine also works wonders with any Proliferate or counter-doubling effect

Her style just differed from what was needed in the upcoming set at the time

The MTG set Ikoria introduced Hexproof counters (along with counters for Deathtouch, Lifelink, and a whole bunch of other keywords) which can be placed on permanents to give them Hexproof