I found out that lunatic cultist treasure bag actually exists in the game files. I was able to cheat it in as an actual item because its there and opened it. the bag doest have any actual loot but there is some gold.
I just realized why summoner. has the lowest defense, the class was made with the intention to allow the player to focus on dodging. summoner is meant to take less hits .
melee on the other hand, is supposed to take hits, that's why they're t a n k y b o i s