How to Mod
With these tips, tricks, & hints you too can mod with the best of them.
How combos form
Heat, Cold, Electricity, and Toxin pair into six secondary elements. Combination follows mod placement: left to right, top row then bottom. Innate weapon elements (and most progenitor bonuses) combine last, after your elemental mods.
- Decide the combo first. Then place the two primaries so they meet in the order you want.
- A leftover primary (Heat next to Viral, for example) is often intentional. Extra random primaries usually make the wrong mix.
- Innate secondaries (a gun that already deals Radiation, etc.) stay. You can still add another combo on top with mods.
Tip
If the Arsenal combo looks wrong, reshuffle slot order before you rip Forma. The Weapon Builder shows the resolved elements as you swap.
Combo table
Each secondary is just two primaries. Order of the pair does not change the result; order on the grid changes what pairs with what when you have more than two.
| Primaries | Combo | Typical use |
|---|---|---|
| Cold + Toxin | Viral | Health damage taken up. Common all-rounder. |
| Electricity + Toxin | Corrosive | Armor strip / armored factions. |
| Heat + Cold | Blast | Knockdown / crowd control flavor. |
| Heat + Toxin | Gas | AoE toxin clouds. Niche but strong in places. |
| Cold + Electricity | Magnetic | Shields. Corpus / shield-heavy content. |
| Heat + Electricity | Radiation | Confusion. Good vs some factions / bosses. |
Mission picks
- Viral + Heat is a common gun pattern for mixed content.
- Corrosive (often with Heat) when armor is the wall.
- Magnetic when shields are the wall.
- Faction and mission still beat "more colors." Plan 1–2 elemental mods on purpose.
Common mistake
Equipping every 90% elemental mod you own. You dilute the procs you care about and often lock in a combo you did not want.