Arena

In the Arena (Not the Event Arena, the Arena), you face off against waves of low-tier enemies and normal gods that are usually accompanied with a single boss. Within the walls of the arena, you cannot die, but you can loot and drink whatever potions or items the bosses and gods drop. Listed below are the notable bosses and few random items that you can get from the arena.

Stheno the Snake Queen,

Septavius the Ghost God,

Archdemon Malphas,

Lord Ruthven,

Thessal the Mermaid Godess,

Bes, Nut and Geb (Tomb Bosses)

Oryx the Mad God (O1).

You can also get the Doku No Ken katana from the large bees that occasionally spawn, at a decent rate. (Perhaps 1/200? No real way to be sure.)