lol wut? is that a new boss?

heres what i do, get the strongest defense armor that u can get.
accessories - all related to dmg, melee, hp acc <-get warding option(+4 def) for each
health - 400hp before plantera, 500 hp after
mana - 200mp

blue horseshoe ballon - good for exploration, useful before wings in hardmode
obsidian shield - keep that, just make it warding so u get that full def option
lightning boots - good exploration stuff again, i usually equip this, but swap out during the boss fights
climbing gear - it's trash imo, i think i equipped magna stone instead of this.