Mount Red Sun arcCaptain Trotter's magma-charge unlocks Firebrand after the lava fall
Mount Red Sun is the second Chapter 4 zone and gates access to The Ancients' tomb via Captain Trotter as the tritagonist-turned-antagonist boss. The fight has two phases: a magma-charge phase where Trotter channels a lava-pool zone under the leftmost target, and a Calypso-sacrifice phase after Trotter falls into the lava (Calypso pushes Trotter into the lava to protect the player, which is what awakens The Ancients as the prophesied final guardian). The Firebrand blade unlocks as a post-Trotter reward once the lava transition completes. The Firebrand card is the Chapter 4 unlock that simplifies the rest of the excavation route, so the Mount Red Sun build should commit to shield-up + self-heal rather than def-pierce - Calypso's sacrifice is the canonical story beat, not an avoidable mechanic.
Excavation templeThe Ancients + Temple Guardian with locked Calypso party
The excavation temple is the third Chapter 4 zone and gates the chapter final boss as Temple Guardian. The route runs The Ancients first (the lower-tomb Final Boss with the lore-heavy Summon Echo mechanic that mirrors the Korbloxian Empire's chief), then Temple Guardian as the chapter final boss. Temple Guardian is the only Chapter 4 fight where the player is locked into a specific ally - Calypso - and the head is invulnerable until both the Left Hand and Right Hand are cleared. The Temple Guardian's signature attack is the orange-mouth laser tell (mouth opens, charges an orange ball, then fires a wide laser that hits every party member). Plan the temple build so The Ancients + Temple Guardian encounters leave enough shield-card coverage for the laser windows, since Calypso goes down hard if you do not peel for her through the second wind.
Finn McCool superbossOptional off-path reward with the Death-Note card drop
Finn McCool is the Chapter 4 optional superboss, hidden off the main excavation path and gated behind a side-quest chain that requires the player to have finished both The Ancients and Temple Guardian first. The fight has the multi-phase shield-pierce rotation that is unique to Chapter 4 superbosses, plus the Death-Note card drop as the post-fight reward. Death-Note is the most-cited Chapter 4 reward in Reddit 'block tales finn mccool' threads because it combos with the Firebrand blade for an Execute-style finisher on later Pit floors. Finn McCool is not required for the chapter clear, but the reward shape pulls steady search traffic from players chasing the full Chapter 4 reward list.
Pit rematchDemo 5's expanded Pit stacks Temple Guardian on Floor 48 and Captain Trotter on Floors 49-50
In Demo 5's expanded Pit of 100 Trials, the Chapter 4 rematch lineup is Temple Guardian on Floor 48 and Captain Trotter on Floors 49-50 as a back-to-back rematch. The Temple Guardian Floor 48 version uses the same mouth-laser tell and Left Hand + Right Hand split phase as the chapter fight, but with tighter timing windows and a forced Calypso ally that you cannot swap out. The Captain Trotter Floors 49-50 version uses the magma-charge phase as the opener and skips the Calypso-sacrifice story beat (Trotter drops on Floor 50 with the Firebrand unlock auto-applied). This is the single best farming route for the Chapter 4 Nirvana badge variants, and the Floor 48-50 trio also pulls 'temple guardian pit' / 'captain trotter pit' Reddit threads from players running the full 60-floor Pit completion.
Badge routeBLOXXER (Chapter 1), Mount Red Sun + Sacred Hollow Nirvana, and the Firebrand loop all live here
Chapter 4 carries three badge families that anchor search traffic. The Mount Red Sun Nirvana badge is tied to the Captain Trotter encounter - the 2025 Reddit refight-every-boss mega-thread calls out Captain Trotter as the badge that requires the Firebrand unlock before the kill, so the badge run cannot start until Mount Red Sun's lava transition is complete. The Sacred Hollow Nirvana badge is tied to The Great Flocci's Free Poison card drop being held in the inventory (the badge requires the card to be in the deck at the moment of the kill, not just picked up). The Chapter 4 Nirvana badge loop runs the Firebrand unlock after Captain Trotter's lava fall - the Firebrand card is the loop runners' reward because it executes the Finn McCool fight in one fewer cycle than a non-Firebrand build. The full Chapter 4 badge list (5 bosses + 5 Nirvana badges + the Finn McCool side reward) is what pulls the steady 'chapter 4 block tales' search traffic every Demo 5 patch.
Build shellOne deck that survives all five bosses without re-speccing
The reliable Chapter 4 shell is one multi-target burst card (to sweep the Temple Guardian Left Hand + Right Hand split phase and to chip the Ancient Summon echoes in the lower tomb), two healing cards (Captain Trotter, Temple Guardian, and Finn McCool each have at least one phase that punishes under-healed parties), one dispel or shield card (to clear the Flocci Spit Poison stacks and to absorb the Temple Guardian orange-mouth laser windows), and one ranged poke card (to break the Captain Trotter magma-charge opener and to handle Finn McCool's shield-pierce rotation). Solo players should swap one heal for a shield - the Temple Guardian mouth-laser phase rewards mitigation over recovery, and a single shield on the laser cast animation is the difference between a clean Chapter 4 clear and a re-run. Use the build maker to confirm BP, SP, heal, dispel, and shield coverage before entering Sacred Hollow or attempting Pit Floor 48.
