For one, your layout takes up much more vertical space than needed. People naturally scan pages in the shape of an F, from left to right, then top to bottom; you do not need to make each individual stat of each individual enemy take up its own line with its own bullet-point, those can be listed to the right of the monster's name. Your use of headers causes the wiki software to automatically add a table of contents, which just takes up space in an article that shouldn't be more than a page long in the first place. You use the same listing header for the enemy's attacks and its charm drops, forcing the reader to rely on locational context for the list's relevance, reducing scanability. (To be fair, that last one's more of a nitpick.)
Everyone works to improve the wiki. I'm very sorry if you feel like I've stolen your work or make it look bad, it was not my intention... But when I saw those big "blocks" of information, populated with so much red links, I felt the will to help make it better, that's all...

The problem isn't adding information. If you're going to go and completely replace a layout someone else made, you damn well better make sure it's better than what was there before. "Don't fix what ain't broke."
dis post brought to you by the letter f, for "lookit that fat design nerd over there, gettin all serious-like over wikipedias! HEH. ehehh"