- Recursion spell: The spell is a trap! If you read it on a scroll or use detect magic on it, the spell infinitely repeats, locking the caster down. It doesn't necessarily have an effect, but eventually the accumulation of magical energy will lead to a violent explosion.
- Memo spell: The spell is cumulative. Every time it is cast, it changes a little bit, in some systematic way.
- Golem: The spell learns, and eventually becomes a living, intelligent spell, a golem spell.
- Null: The spell is neither yes nor no, it defies binary logic.
- Papers, Please: The spell causes two players to switch character sheets (they are still the same character, just with different stats).
- We're playing different games: The spell causes a player to rewrite their character sheet for a different game (just one player). We're all adults here, figure it out.
A couple of these are ideas you might notice I've played with before, but I tried to stick to the rules of the challenge and keep it to mostly things I haven't done before. This list turned out better than I expected.