I have been looking for a game for MONTHS that used to be through adobe flash. I also think that it was on cool math at some point. You played as a blue ghost guy that used to wear a cloak. You had to be quiet and stealthy to sneak up on these guards that wore robes. They held fire or ice spears. It was in a castle setting. I found a picture of it but no name, I can send it if anyone needs. Thank you! 🙂
Source: https://www.reddit.com/r/oldgames/comments/ru2qha/please_help_me_find_this_old_game/