To ensure supply is similar, I compare cards of the same set and rarity
This is especially common in GUx towns, as their in-color options are a bit worse
It could be worth the drawback of giving your opponent ink if it removes a high-value Item card your opponent is counting on
After lessons are cast they behave as regular instants or sorceries, so they go to the graveyard when they resolve
10 Mickey Mouse, Wayward Sorcerer (Enchanted) - $186.16 Set One, The First Chapter Broom characters are fairly easy to come by and can be disposed of by your opponent with relative ease, but stacking them up whilst keeping this Mickey card in play is quite an annoying strategy
The name perfectly encapsulates the effect - it counters any target spell, period