As the Vault Hunters approach 5H4D0W-TP after entering Deck 13.5, 5H4D0W-TP summons Claptrap's Consciousness and offers him the option of integration to ensure the destruction of Claptrap's enemies, an offer that is refused. Resigning to the fact that Claptrap will die no matter what unfolds following this decision, 5H4D0W-TP informs the Vault Hunters that he will splice himself with the H-Source code, thereby gaining the upper hand in their second encounter. Upon splicing with the H-Source, ECLIPSE begins to form around 5H4D0W-TP and boots up as the Vault Hunters express their disbelief.
ECLIPSE is a formidable opponent with a large health pool and dangerous attacks. It additionally has turrets mounted on its body which provide it with even more offensive capabilities, though those can be targetted and destroyed to help mitigate their danger. Bugs, Glitches, and other enemies will spawn during the battle and can be used to provide Second Winds to any Vault Hunter sent into Fight For Your Life.
Once ECLIPSE has been defeated, 5H4D0W-TP will reconfigure itself into the final boss of the DLC, EOS.
- Main article: System Shutdown
- In addition to dropping an assortment of loot of various rarities and Moonstones upon defeat, ECLIPSE will always drop one glitch gun of random weapon type.
- Due to its raid boss scaling health pool, player should be well prepared for the long fight. multiple types of corrosive weapons can be brought for mitigate running short of ammo.
- ECLIPSE becomes extremely difficult to fight during co-operative play. This is due to the fact that during co-op, ECLIPSE periodically launches homing missile volleys that seek out a random Vault Hunter and inflict massive amounts of damage. These missile volleys are in turn occasionally glitchy - during some sessions of play, one or two missiles may be launched at a time, with several seconds between each volley. Other times, the missiles may be launched in a nearly never-ending barrage.