Thesaurosus

Thesaurosus is a stationary dragon boss encountered on a dense, coin-filled pegboard themed as a treasure hoard. The board contains a high concentration of coin pegs and other pegs clustered into a pyramid mound, making it both an opportunity for large multi-hit damage and a hazard when refresh or critical pegs become buried. Thesaurosus’ lore describes him as impossibly avaricious: much of his hoard was stolen from the peglins, but treasures from across Radia are contained in his lair.

In combat Thesaurosus remains in place and uses a pull-and-breath pattern. When he initiates his breath attack he exerts strong pull force toward a board exit; this pull can drag the player toward him and also applies substantial pull on an orb exiting the board. When an orb enters the exit while the pull is active Thesaurosus gains charge (1 charge normally, 3 at Cruciball 20). If the player is pulled close enough he charges and unleashes a Fire Breath that hits in a four‑hit burst of 3 damage per hit for a total of 12 damage. After the fire breath he follows with a Claw Attack that deals 20 damage, pushes the player back to their starting position, and shuffles all pegs on the board into a new pyramid configuration. These actions repeat for the duration of the fight.

Practical notes and strategies:

• The treasure board’s dense peg mound makes multi-hit effects and concentrated piercing attacks valuable. Concentrication (piercing) helps reach refresh and critical pegs buried deep within the mound.
• Intentional Oboe is particularly effective because its per-hit damage reduction interacts strongly with multi-hit attacks, reducing their effectiveness against the boss’s defenses less than single large hits.
• Magnet orbs and magnet relics (for example, Electorbmagnet or Electropegnet) perform well because the board layout often forces orbs to the side; magnetism pulls orbs back toward the center for better peg coverage.
• Gold relics that boost damage (such as Peglinero's Pendant) are helpful early since the board is dominated by coin pegs.
• Bring refresh solutions or other ways to expose buried refresh_peg sources; without them the player can run out of resources on the dense board.
• Inflicting Blind prevents the 20-damage Claw Attack, though it does not affect the Fire Breath burst.
• Sustain effects and income (Infernal Ingot, Popping Corn, Ballwark) enable long-term survival because Thesaurosus’s attacks and behavior are non-scaling, allowing players to outlast the encounter with sufficient healing and mitigation.
• Note that in recent versions the board reshuffles on the Claw Attack; earlier changes increased the boss’s health and adjusted spawn locations for special pegs.

Trivia: Thesaurosus’ name is derived from a Latin-based pun meaning “Treasurer,” rather than being related to the English word “thesaurus.” The Qaballistic Ruins variant has a larger health pool but presents an even harder board for dealing damage.