Any Way to Spawn Bosses/Use HFS To Create Items?

Hi there! I've been looking through the HFS files but there's just too many of them that I thought it would be a little helpful to just ask here directly in case someone has already discovered a method on the things I'm interested in.

First, is there a way to spawn bosses? I remember a few weeks ago seeing a picture that showed three giant bears at once. I'm not sure if that was a photoshop trick or not but I'd like to try and take on multiple bosses at once or spawn tag teams of them that shouldn't be possible. I imagine it would be fun lol

Second, is there a way to create items with the help of editing HFS files? The last time I tried editing them was when I changed the Premium Rookie clothes into Dark Crest (I changed the names in the file). Unfortunately, that didn't work. I also tried changing crafting material requirements for little things like Blessed Magic Powder and Fine HP Potions, but when I checked, they still required me the original amount of stuff, so my idea didn't work.

Thanks whoever can share info about these, have fun