Blade of Cosmosa

Equipped creature gets +1/+1 for each counter
on it and can block creatures with spaceflight.
Equipped permanent isn't a planeswalker and is a creature in addition to its other types. (Loyalty abilities can still be activated.)
Equip Planeswalker {1}, equip {3}
A weapon that only answers to Cosmosa's hero.
https://youtu.be/cV_ZvMV2MM0?si=BuhCWatV_xwBORss