Swamp Man (final)

Chapter: EoZ · End of Zoe: from the Swamp to the Main House (Joe)
Where: Baker Estate, Main House: the Main Hall

Weak point

Only charged left punches from the AMG-78; the guides aim at the head

The final boss of End of Zoe. Only charged left punches from the AMG-78 hurt him; Joe can't block while charging and any hit cancels the charge. It is the only End of Zoe fight whose HP changes with difficulty: 16,000 HP on Easy, 14,500 on Normal and 11,000 on Joe Must Die. Save and use the Item Box at the Yard entrance; bring every critter and turn your materials into Throwing Spears or Stake Bombs.

Reward

The ending of End of Zoe: Zoe gets the cure. "Promise Kept" (Easy or Normal) or "King of the Swamp" (Joe Must Die) achievement.

16,000 / 14,500 / 11,000 HP by difficulty (datamined). The AMG-78a does −87.5% on Easy and Normal: use the story AMG-78. Per the same data the head takes −50% on Easy and Normal, although the guides say to punch it: hit whatever you can reach without risking the charge.

Step by step

Pick up the 2 First Aid Meds on the benches (SW and NE corners) before you approach Zoe: examining her starts the fight.
Charge the left (hold ZL) away from him and release it between swipes.
Horizontal tentacle: crouch, but not too early or he aims low. Vertical tentacle: step left. His tentacles reach far and hit very hard.
Phase 1: when he drops to one knee, a fully charged punch knocks him down and starts phase 2.
Phase 2: he is faster and chains tentacle combos. If he takes a judo stance with his hands raised, don't punch: he counters everything.
Pre-charge, back off and strike between swipes until the finisher: Joe crushes his skull.