Yesterday, a handful of players were jailed for griefing the Pikachu and Squirtle outside spawn. One of the players is on currently, and is very understanding of their jailing-- however, they mentioned that Rule 8 only states, "No breaking blocks in or near a base." Since the pixel Pokémon weren't bases, per se, this player was confused as to what they were and weren't allowed to break.
I feel like he should have known better than to break the blocks, but it may be helpful to add something to rule 8 that includes information about it being against the rules to break blocks included in any structure that you didn't create, not just others' bases.
Just a thought!
Edit: Jordan pointed out that rule 1 states (very clearly) "No griefing at all!"