Shadow Labyrinth presents significant challenges, making your HP Tank an essential survival tool. Unlike similar items in other games, the HP Tank in Shadow Labyrinth fully restores your health. Initially, players only have access to one such tank, which can be limiting in prolonged encounters.
A crucial second HP Tank can be found in the game`s second major region, which requires ascending the Sky-high Tree. This vital upgrade is easily overlooked, especially if you progress quickly. To avoid unnecessary backtracking, follow this guide for its precise location and acquisition steps.
Locating the Second HP Tank
The second HP Tank is situated within the forest section of the Great Tree (also known as Sky-High Tree). Your journey begins in the Sky-high Tree Front area. As you advance through this level, you`ll encounter a lengthy path in the western corner, leading to a higher region and eventually a major boss. However, before that final encounter, you must defeat an interim boss. The second HP Tank becomes accessible after you defeat Duke Sirius.

From the central checkpoint in the Duke Sirius arena`s vicinity, continue following the path to the right. This path leads directly to the boss fight. If your GAIA form charge is low, it`s advisable to defeat nearby enemies to replenish your energy before engaging Duke Sirius.
Duke Sirius Battle Strategy
Duke Sirius employs three primary attacks:
- Leap and Slam: As a bird, Duke Sirius frequently attempts to close the distance by leaping and slamming the ground.
- Whirlwinds: The boss generates small whirlwinds by flipping its wings, which can appear singularly or in pairs.
- Fire Spit: Duke Sirius can spit fire, covering the ground on both sides of its position.

A highly effective strategy involves initiating your attack as Duke Sirius descends into the arena. Capitalize on its introductory animation to land multiple hits, utilizing your `basic attack, basic attack, strong attack` combo. Be ready to dodge immediately afterward as the boss retaliates.
When Duke Sirius creates whirlwinds, utilize the arena`s side walls for vertical maneuverability and attachment points. If multiple whirlwinds persist, observe for an opening to maneuver past them. Once Duke Sirius`s health is approximately halved, activate your GAIA form and continuously attack. The GAIA form is potent enough to deplete the remaining health bar swiftly.

Acquiring the HP Tank
Upon defeating Duke Sirius, a long vine will become accessible to the right of the arena. This vine leads to a higher structure, where you can follow a path to the left. Before ascending, however, ensure you drop down from the arena floor to the area below. The second HP Tank is located there, visible on your map as a red question mark.
This HP Tank is often overlooked because its map marker and in-game icon resemble less significant collectibles. Therefore, prioritize collecting this item, even if you typically skip others. If you`ve already progressed past this point, you can easily teleport or backtrack to the Duke Sirius encounter area to retrieve it. Acquiring the second HP Tank automatically refills your primary HP Tank, allowing you to continue your journey immediately, even after a challenging battle.