Give the Leviathan Flail nine Area mods and one Speed mod. This will be one of the best weapon configurations if you can handle it. Use the Charge Boots to get closer to an enemy, then smash it. Most of them they will be dead with one hit. If not, use the Freeze mod as an Omega mod for bigger enemies. This is the best option for all arena battles, because one smash in the mid almost destroys everything. This weapon configuration is also very effective for small rooms and other narrow or small places. Do not worry about the ammunition. If you smash one time, three ammo boxes will be broken to refill the flail's ammunition. Use the Hypersmash if you get too surrounded (jump then smash). If this is done, the front and rear will be smashed.