SOs, IOs, sets, attuned, boosters, catalysts: the game introduces each of these in a different decade of its life and never explains how they relate. This page is the missing manual. Ten minutes here and the enhancement screen stops being a puzzle.
1. The short version
Boosting buys the highest numbers; attuning buys where the numbers work. A crafted level 50 set piece plus five Enhancement Boosters is the strongest an enhancement gets (level 55 effectiveness). An attuned piece never beats a plain level 50 one - what it does instead is scale with your level and keep its set bonuses when you exemplar down. You cannot have both on the same piece: attuned pieces cannot be boosted.
- Character you exemplar or level with: attuned.
- Level 50 character that stays 50: crafted + boosters.
- Leveling on a budget: SOs, upgraded as you go - a perfectly good road all the way to 50.
2. The store ladder: TO, DO, SO
Training, Dual and Single Origin enhancements are the ones stores sell. Each improves one aspect of a power (accuracy, damage, recharge and so on); each tier is roughly twice as strong as the one below; and each has a level. Outlevel a store enhancement by more than three and it stops working, so leveling with them means periodically replacing the tray. That upkeep is their real price, and it is also why they are cheap.
SOs are the strongest store tier, and a tray of current SOs is completely respectable: the classic "SOs until 50, then build for real" path works fine. The analyzer's build check will tell you what a set would add, but "later" is a legitimate answer.
3. Common IOs
Invention Origin enhancements are crafted (or bought off the Auction House) rather than store-bought. A common IO does the same single-aspect job as an SO with two differences: it is a bit stronger at comparable levels, and it never expires. A level 30 common IO slotted at level 30 keeps working at 50. Slot commons once in the late 20s or 30s and you can stop paying the SO replacement tax forever.
4. Enhancement sets
Set IOs are where builds start being designed. Each piece of a set enhances several aspects at once (Accuracy/Damage in one slot), and slotting multiple pieces of the same set in one power grants set bonuses: global defense, recharge, recovery and more, stacking across your whole build. When the build check says a set is "the cheapest bonus real estate", this is what it means: the same six slots you were already using start paying rent.
Each set works over a level range and belongs to a category (melee damage, holds, defense...); a power accepts sets of its own categories. Some pieces are special: procs (a chance to fire an extra effect instead of enhancing numbers) and uniques (one copy per build).
5. Attuned pieces
An attuned set piece has no level of its own: its enhancement values track your level (up to the set's own maximum), and its set bonuses work all the way down to the set's minimum level when you exemplar. Buy set pieces already attuned on the Auction House, or convert a crafted piece with a Catalyst.
Two things attuning does not do: it does not make a piece stronger at 50 (an attuned piece at 50 equals a plain, unboosted level 50 one), and it does not allow boosting - attuned pieces cannot take Enhancement Boosters at all. Attuning trades the ceiling for the floor.
6. Enhancement Boosters (+5)
A Booster raises a crafted IO's effectiveness by 5%, up to five times: a "level 50+5" piece performs like a level 55 one. That is the highest ceiling in the game, and the whole reason min-maxed level 50 builds use crafted rather than attuned pieces.
The catch is that boosting does not change the piece's real level. A boosted level 50 piece still counts as level 50 for exemplar purposes, and set bonuses stop working when you exemplar more than three levels below a piece's level - so that 50+5 goes quiet on a level 30 task force, exactly when an attuned piece would keep paying out.
7. Enhancement Catalysts
A Catalyst upgrades a piece in place, and it does two different jobs depending on what you feed it:
- On a regular crafted set piece: converts it to the attuned version (one way - there is no un-attuning; to boost again you would buy or craft a new crafted copy).
- On an Archetype or Winter set piece: upgrades it to its Superior version, with higher values and stronger bonuses. This is the main endgame use of Catalysts.
Archetype (ATO) and Winter pieces are attuned by nature: they already scale with your level and they can never take Boosters. For those sets the Catalyst question is only "regular or Superior".
8. Which should you use?
- Leveling a new character
- SOs upgraded on the go, or common IOs around the 30s to stop the upkeep. Attuned set pieces work while leveling too if you want bonuses early - they grow with you.
- A character who exemplars often (task forces, themed teams, Ouroboros)
- Attuned set pieces everywhere you care about bonuses. ATO and Winter sets shine here: attuned by nature, and their bonuses reach low.
- A level 50 that stays at 50
- Crafted pieces with Boosters. This is the maximum-effectiveness build: every piece at 50+5.
- Very rare ("purple") sets
- Only slottable at high level, and their set bonuses keep working when you exemplar regardless - so there is no reason to attune them. Boost them.
9. The traps that catch everyone
- "Attuned must be stronger, it says it scales." No: at 50 an attuned piece equals a plain level 50 piece. The strongest option is crafted + Boosters; attuned is the most flexible option.
- Boosting an exemplar build. Boosters raise a piece's numbers, not its level: a 50+5 still counts as level 50, so its set bonuses stop below 47 - exactly where an attuned piece would keep going.
- Trying to boost an attuned or ATO/Winter piece. Not possible, by design. If you want to boost a regular set piece you attuned earlier, you need a fresh crafted copy.
- Catalyzing a purple. Purple bonuses already survive exemplaring, so attuning one gives up the Booster ceiling for nothing.
- Forgetting SOs expire. If your damage suddenly feels weak mid-30s, check the tray: outleveled (red) enhancements have quietly stopped working.
Figures and flags on this page (what can be boosted, what attunes, what catalyzes into what, set level ranges) come from the game's own data files, the same source the analyzer uses for its build advice.
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