Block-Trolls were a creature that was supposed to be added with Dire Game Reviewers and Game Reviewers. They never got implemented however.
TEXT FROM THE 8BITMMO BLOG:
Jul/13/23
Upcoming update… with 3x new mobs![]
The next update is going to be pretty big. Not only will it have the swords, it will also have at least three new mobs & their accompanying spawners. This week I re-wrote how melee mobs are handled, so it's a lot easier to add new ones. Health will increase with each level. I plan to release all this the week after next week (probably around 8/6)... hopefully by then, the new dungeons are ready to go.
Yes you will get to fight Game Reviewers. Hehehehe :D