Common item (white). What the game says, what it really does, what each copy adds and what it pairs with.

Backup Magazine
Common item (white)
Your secondary skill (right click) gets one more use before its cooldown. Each extra magazine, one more.
Game text: «Add +1 (+1 per stack) charge of your Secondary skill.»
Stacking: Each copy adds the same, no cap.
Watch out: More uses, but it does not lower the secondary cooldown. Lets Engineer place more mines.
| 1 copy | 2 copies | 3 copies | 5 copies | 10 copies |
|---|---|---|---|---|
| 1 | 2 | 3 | 5 | 10 |
Each copy adds the same.
more Nano-Bombs or Nano-Spears in a row: her big damage.
with several, Corrupted Flood can be spammed.
more mines.
with Nano-Spear, it can freeze Mithrix over and over.
with several, Corrupted Flood can be spammed and even keeps you airborne.
Your secondary skill (right click) gets one more use before its cooldown. Each extra magazine, one more.
Stacking: Each copy adds the same, no cap.Watch out: More uses, but it does not lower the secondary cooldown. Lets Engineer place more mines.
Sources: the game's English text (name and description), the Risk of Rain 2 wiki (riskofrain2.wiki.gg: this item's page, read on 31 October 2026; numbers, stacking formula and notes) and the wiki's survivor pages. The plain-words text and the synergies are ours. Icons: Risk of Rain 2 (Hopoo Games / Gearbox).