Unlocking skills and abilities in Phantom Blade Zero requires more than just accumulating a standard in-game currency like Remnant Dust. Players will need to explore the world and collect specific items, as certain perks are gated behind progression and acquired upgrades.
The game's skill system is organized into three primary categories or rows, which must be unlocked sequentially from left to right. These rows are directly tied to specific collectibles: Blackstone for attack upgrades, Sha-Chi Amber for energy upgrades, and Memory Flowers for health upgrades. For example, a particular skill might necessitate having collected four units of Blackstone, meaning a total of sixteen Blackstone Fragments must be found through exploration.
Some of the more advanced abilities will only become available later in the game, after players have thoroughly explored nearly every area. The skill tree's second and fourth rows represent interconnected perks. These can be activated only after the player has unlocked the associated nodes and possesses sufficient Banyan's Hearts. Banyan's Hearts are acquired by completing Banyan Tree encounters, which feature waves of enemies and boss fights. A limited number can also be purchased from Quick Hand Zhang for 100,000 Remnant Dust each. There are eight Banyan's Hearts in total, with one corresponding to each interconnected perk or node.
Acquiring the necessary upgrade materials, such as Memory Flowers, Blackstone Fragments, and Sha-Chi Amber, is crucial for character progression. The game also features a weapon and gear upgrade system, allowing players to further enhance their equipment.