Last one Standing Side Quest is available anytime. This task can not be completed on your first playthrough.
|Last one Standing|
|Reward(s)||12000 gil, Weapon Bladed Lanc, Hermit's Cap, Max HP +160, Strength +18, Magic +16|
Go and talk to Zanford, man below the Oasis Lighthouse, You may not be able to complete ths task on your first playthrough. You are tasked to kill every Omega enemy in the game, and three Omega enemies only appear in last storyline dungeon - grand total is 31 Omegas. Also you need to kill afro-cactuar and Ereshkigal on floor 33 of Ultimate Lair.
Once you are done go and talk to Zanford to complete the mission