Trace MaterialKey of Knowledge
Key of Knowledge is a 3★ material in Honkai: Star Rail. See how to get it and which characters/light cones need it below.
Key of Knowledge is a material ★3 in Honkai: Star Rail. 6 characters need this item to level up. 12 Light Cones need this item to level up. Obtainable from 4 different sources in-game.
Last updated: 30/07/2026
The figures on this page come directly from gamevika's internal game data store (counted/read straight from the real records), not an estimate or copy from elsewhere.
Description
A mythical key that appears in the hands of the sages of the worlds. Used to level up Traces moderately for Erudition characters.
Lore
It can unlock the mysteries binding the truth of the world and grants knowledge beyond the understanding of humans. No matter how the wielder attempts to display their possession of the key, no one but themselves can see its form. Some people believe that to be a gift from the heavens, while others think it's a sign of mental disorder. "I had a dream of molecules coiling up into a loop like a snake biting its own tail. I woke up realizing that this is the answer I've been looking for all along!"
Farm it smart
A Trace (skill tree) material. Harsh truth: traces devour materials late-game, especially levels 8–10. Do not level evenly — pour into Skill/Ultimate (your main damage) first, Basic ATK last.
Material Planner →How to obtain
- Calyx (Rivet Town)
- Omni-Synthesizer — Material Synthesis
- Embers Exchange
- Omni-Synthesizer — Material Exchange
Used to upgrade
Used for Light Cones
Stats
| Rarity | ★★★ |
| Type | Trace Material |
| Stack limit | 99,999 |
Official names in every language
| Tiếng Việt | Chìa Khóa Tri Thức |
| English | Key of Knowledge |
| 日本語 | 啓発のカギ |
| 한국어 | 계몽의 열쇠 |
| 繁體中文 | 啟迪之鑰 |
| 简体中文 | 启迪之钥 |
Where to use it / Related tools
Key of Knowledge is an upgrade material — check the Material Planner to see how much you need for the character you're building.
Same-type items
FAQ
What is Key of Knowledge?
A mythical key that appears in the hands of the sages of the worlds. Used to level up Traces moderately for Erudition characters.
Where do you get Key of Knowledge?
Sources for Key of Knowledge: Calyx (Rivet Town) · Omni-Synthesizer — Material Synthesis · Embers Exchange · Omni-Synthesizer — Material Exchange. See the “How to obtain” section above for details on each source.
What type of item is Key of Knowledge?
Key of Knowledge is a 3★ material in Honkai: Star Rail, in the “Trace Material” category.
What is Key of Knowledge used for?
Key of Knowledge is used by 6 characters, 12 Light Cones.