Sansyrus17
Skeletron
All you're going to need is a good armor for rangers, a phantasm (a good reforge won't be that useful exept you want REALLY high speed personally i used it with an unreal reforge) luminite arrows or bullets (if you're using a gun) a stardust dragon for a small dps boost a depth metre and a ufo mount. Dig a straight hole that leads to the spot whith zero depth and a little more so thar the dungeon gurdian actually spawns (i recommend using a luminite pickaxe for it's extra range) and not go under 2 Underground so he won't spawn while you're unprepared i also stronly recommend clearing a LARGE space around the world (like space islands and living wood trees). Then all you need is to go down WITH THE UFO MOUNT and as soon you hear the noise that announces he's spawn you imediately press space (or W) take some buffs (like endurance and wrath) and start going crazy with the phantasm (or anything else) if he's too close to you you can easily make ankle moves to avoid being hit. WITH A PHANTASM i personally reached over 100 dps sometimes (WHICH IS ABSOLUTELY INSANE) i managed to kill the gurdian twise in expert mode because two of them spawned and because i didn't have another world where i haven't beaten Skeletron (i actually didn't have another world exept my normal one and the one in expert mode and i was too bored to make a new one) and i managed (after a couple deaths) i beated that tank. If you've red this whole thing you're amazing and thank you so much.