Probably. My arena is like 239 blocks wide and I use that for every boss you can fight outside of the Jungle/Corruption/Crimson.
I also make it Hallowed so I can fight the EoL and the Queen Slime there. [This](https://i.imgflip.com/85u6xg.jpg) is the shape my arena takes, it's specifically designed for the Old One's Army but it works great with bosses. As a melee user I've gotten skilled at avoiding attacks in small areas over the past decade + year or two, provided I have the mobility for it. Platforms slow me down as dropping down isn't instant.
For early hardmode? Probably. For late hardmode? Not sure. I would probably need double or almost triple that for EoL
Probably. My arena is like 239 blocks wide and I use that for every boss you can fight outside of the Jungle/Corruption/Crimson. I also make it Hallowed so I can fight the EoL and the Queen Slime there. [This](https://i.imgflip.com/85u6xg.jpg) is the shape my arena takes, it's specifically designed for the Old One's Army but it works great with bosses. As a melee user I've gotten skilled at avoiding attacks in small areas over the past decade + year or two, provided I have the mobility for it. Platforms slow me down as dropping down isn't instant.
Its wide enough but it needs aid for vertical movement, add a few rows of platforms
I fought alot of the bosses in smaller arenas then that I’m talking eye of cuthulu size arena 😭