mtg cards like walking ballista (Halo Foil) Put a +1/+1 counter on Walking Ballista.Remove a +1/+1 counter from Walking Ballista 1x Walking Ballista Rare, Aether

For example, in Urza's Destiny (the set where I was the entire design team), there were two different cycles that explored effects that scaled based on how many cards of a certain color were in your hand

This can also 2 mana tap to copy a triggered ability like Hellkite Charger or Solemn Simulacrum but also an activated ability like Aggravated Assault

The looting pushes this card over the top

And of course there are plenty of rats, since that's a Wilds of Eldraine draft archetype

There are those that give card quality or draw cards, there are cards that do specific things while being on reasonably costed tempo dorks and there are powerful effects tempered by drawbacks that may be used to good effect in times of need