Thanks for playing!
I'm not sure which block you mean. The engine I used has a bug that sometimes renders the wrong tile so that might have been it.
I'm not sure where that sprite comes from, it could be junk in the memory, but I do have a pickup that spawns there. I removed the pickup since I couldn't get it to work before the end of the jam. I guess I left something there and the game is rendering whatever is in memory.
I'm planning to continue work on the game. When I get the pickup to work it should fix the problem.
Thanks for the feedback. Much appreciated!