Cyclops

The Cyclops is a Boss you encounter if you chose to do the Quest in Chapter 2: Storm Island. It is a very strong boss with various attacks that can be tricky to avoid when not prepared.
It is best not to face him before level 7 or 8 since you will need to do a lot of damage to defeat him before the quest ends. He has a lot of base armor but it can be knocked out, leaving a possibility to deal a high amount of damage for a short duration.