Avogadro

Avogadro is a boss mole enemy encountered in Peglin that uses a central tree and spawned Euphorbia plants to shield itself and pressure the player. In combat Avogadro spends several turns hidden behind the tree in the center of the enemy area, then burrows next to the player to strike and immediately retreats behind the tree to spawn a Euphorbia. Defeating Avogadro ends the encounter even if other enemies remain. Each time Avogadro retreats behind the tree he causes bombs (bomb_regular) to appear in the tree's leaf tiles on the pegboard; these bombs reliably spawn as the mole plants new minions and constitute a predictable board feature of the fight. Hitting the tree with an attack that reduces its health by more than 25 also grants Avogadro a Muscircle (one at Cruciball 0–19, two at Cruciball 20), which increases its offensive capability.

Avogadro's attack pattern and plant-spawning behavior have a few concrete timing details to exploit. He will remain behind the tree for at least three turns before burrowing to the player for a melee attack (historically damage values have changed across versions; the current base attack is 8). He will burrow back to the player one turn after the plant directly in front of the player dies, and on every third turn of his cycle he will swap places with a Euphorbia if one occupies the tree-front space. Bombs appear in the tree when he moves behind it, and killing the tree no longer counts as killing Avogadro for achievement purposes.

The fight favors strategies that bypass or mitigate the tree and the spawned minions while taking advantage of the recurring bombs:

• Piercing and targeting orbs are highly valuable because they can ignore Euphorbia minions and damage the mole or hit the tree despite blocking minions. They shorten the fight by reaching priority targets without being stopped by plants.
• Bomb-focused builds and relics synergize with the guaranteed bomb growth on the board. Use bomb relics or bomb-damage synergies to convert the tree-bombs into reliable extra damage.
• Sustain and single-target healing reduce attrition: bringing Doctorb(s) helps offset repeated hits from Avogadro when the fight drags on.
• Damage-increasing orbs and units such as Swoltorb improve kill speed, especially when combined with piercing orbs to avoid minions.
• Applying bramble to the tree-front tile prevents Avogadro from burrowing behind the tree momentarily, but be aware that bramble causing him to remain in front of you will make him attack every turn for his melee damage; avoid bramble that pins him in the front if you cannot kill him quickly.
• Manage orb discards with the mole's attack rhythm in mind so you use high-value orbs on the turns he emerges rather than wasting them while he is reloading behind the tree.

Lore notes: scholars in-game describe a symbiosis between forest moles and Euphorbia plants, explaining why Avogadro cultivates these minions rather than relying purely on direct attacks. The boss name and its health values reference Avogadro's Constant and the mole SI unit. Version history shows multiple balance adjustments since introduction (v0.5.56), including changes to health, attack damage, and the Muscircle mechanic added in later updates.