TBH Cube System Guide
On this page
- Cube Overview
- All 8 Cube Functions
- Best Cube Feature Unlock Priority
- Synthesis Deep Dive
- Alchemy Strategy
- How to Level Your Cube Fast
Cube Overview
The Hero-dric Cube is TBH's item customization and upgrade system. Think of it as a workbench where you can upgrade, modify, sell, and extract value from your gear. The Cube levels up independently from your heroes — every operation grants Cube XP, and higher Cube levels unlock more powerful functions. Cube Level 10 is the most important milestone because it unlocks both the Extraction feature and Steam Market access.
All 8 Cube Functions
| # | Function | Unlock | Gold Cost | What It Does |
|---|---|---|---|---|
| 1 | Alchemy | Cube Lv.1 | 10 Gold | Convert unwanted gear into gold. Grants Cube XP. Your main gold source for Rune Tree upgrades. Always alchemize Common and Uncommon items. |
| 2 | Synthesis | Cube Lv.1 | Free | 9 items of same rarity → 1 higher-rarity item. Core upgrade mechanic. Output type is random — use same-type inputs for controlled output. |
| 3 | Crafting | Cube Lv.5 | 100 Gold | Use materials to craft gear of a specific slot. Primary way to get accessories (rings, amulets, bracers, earrings) which drop extremely rarely from monsters. |
| 4 | Decoration | Cube Lv.8 | 300 Gold | Socket gems for random bonus stats. Rare gear gets 1 slot, Legendary+ gets 2 slots. WARNING: stats are wiped when listing on Steam Market. |
| 5 | Extraction | Cube Lv.10 | 1,000 Gold | Remove attached effects from gear. Materials are NOT returned — only frees the slot. Use before selling decorated/engraved items on Steam Market. |
| 6 | Engraving | Cube Lv.15 | 1,000 Gold | Guaranteed stat bonuses for Legendary+ gear. No RNG — you choose the stat, you get the stat. PERMANENT — cannot be transferred. |
| 7 | Offering | Cube Lv.20 | 3,000 Gold | Offer commemorative coins to draw random items. Coins are rare — save them for events or when you specifically need a boost. |
| 8 | Inscription | Cube Lv.25 | 10,000 Gold | Add random stat options to gear via scrolls. RNG-based. Use on mid-tier gear; save Engravings for your best items. |
Best Cube Feature Unlock Priority
- Alchemy (Lv.1) — Start converting trash gear into gold immediately. The 10g fee is negligible.
- Synthesis (Lv.1) — 9:1 upgrade mechanic. Available from the start. Use it.
- Crafting (Lv.5) — Fill empty accessory slots. Crafting is the most reliable accessory source.
- Extraction (Lv.10) — Steam Market access + ability to strip Cube attachments before selling. This is the most important Cube milestone.
- Decoration (Lv.8) — Random bonus stats. Use on gear you plan to keep long-term. Comes before Lv.10 chronologically but Extraction is more impactful.
- Engraving (Lv.15) — Guaranteed stats. Premium but reliable.
- Offering (Lv.20) — Coin-based draws. Save coins for when you need them.
- Inscription (Lv.25) — Endgame RNG stat rolling. Expensive. For min-maxing.
Synthesis Deep Dive
The core rule: 9 items of the same rarity → 1 item of a higher rarity. The output is always random — you don't get to choose the slot or class. This is the tradeoff: guaranteed rarity upgrade, but random output. Use 9 items of the same type (e.g., 9 Rare Swords) to guarantee the output type — 9 swords always make 1 sword.
Synthesis Success Rates
| Input Rarity | +1 Tier | +2 Tiers (Lucky) | Same Tier (Fail) |
|---|---|---|---|
| Common | Uncommon 95.24% | Rare 4.76% | — |
| Uncommon | Rare 96.15% | Legendary 3.85% | — |
| Rare | Legendary 97.56% | Immortal 2.44% | — |
| Legendary | Immortal 99.01% | Arcana 0.99% | — |
| Immortal | Arcana 49.88% | Beyond 0.25% | 49.88% |
| Arcana | Beyond 33.28% | Celestial 0.17% | 66.56% |
| Beyond | Celestial 23.06% | Divine 0.08% | 76.86% |
| Celestial | Divine 16.66% | Cosmic 0.02% | 83.32% |
| Divine | Cosmic 9.09% | — | 90.91% |
The Immortal Wall: Starting at Immortal, "same tier" chance appears and grows rapidly — 50% at Immortal, 67% at Arcana, 77% at Beyond, 83% at Celestial, and 91% at Divine. High-tier synthesis is a grind. Synthesize in bulk to smooth out the variance.
Expected cost to reach Cosmic from Common: approximately 340 million Common items and 38 million synthesis attempts. Cosmic tier is the ultimate long-term goal — don't expect to reach it quickly.
Alchemy Strategy
| Rarity | Alchemy Gold | Better to... |
|---|---|---|
| Common | 3–5 | Always alchemize. Infinite supply, gold + Cube XP. |
| Uncommon | ~10 | Always alchemize. Your main gold engine. |
| Rare | ~25 | Alchemize extras. Save 9 for synthesis if close to a stack. |
| Legendary | ~80 | Check Steam Market first. Even a mediocre Legendary can sell for more than the alchemy yield. |
| Immortal | ~250 | Steam Market candidate. Price check before alchemizing. |
How to Level Your Cube Fast
- Alchemize everything Common and Uncommon. Volume is your friend — hundreds of cheap items add up to significant Cube XP.
- Synthesize whenever you have 9 of the same rarity. Synthesis also grants Cube XP.
- Save Offering coins for XP bursts. Commemorative coins grant large Cube XP when offered.
- Don't skip alchemy to save the 10g fee. The gold you get back from alchemizing covers the fee, and the Cube XP is pure profit.