Hell's Park Underside
Before challenging a stage, its difficulty level can be selected. Higher difficulties will increase enemy levels, add skills to the enemy, and add team-building restrictions.
When a stage is cleared, the player receives the reward for that level, as well as the rewards for all levels below it. These rewards reset monthly.
Initially, only 10 difficulty levels are available for each stage. Clearing level 10 on a stage unlocks levels 11-20 for that stage, clearing level 20 unlocks levels 21-30, and so on.
| Level | Gold | Silver |
|---|---|---|
| 1 | ?? | ?? |
| 2 | ?? | ?? |
| 3 | ?? | ?? |
| 4 | ?? | ?? |
| 5 | ?? | ?? |
| 6 | ?? | ?? |
| 7 | ?? | ?? |
| 8 | ?? | ?? |
| 9 | 5 | 300 |
| 10 | 5 | 300 |
| 11 | - | 100 |
| 12 | - | 100 |
| 13 | - | 100 |
| 14 | - | 100 |
| 15 | - | 100 |
| 16 | - | 100 |
| 17 | - | 100 |
| 18 | - | 100 |
| 19 | - | 100 |
| 20 | - | 100 |
| 21 | - | 30 |
| 22 | - | 30 |
| 23 | - | 30 |
| 24 | - | 30 |
| 25 | - | 30 |
| 26 | - | 30 |
| 27 | - | 30 |
| 28 | - | 30 |
| 29 | - | 30 |
| 30 | - | 30 |
Notes
- Gold badges seem to only come from the first 10 levels of each area. After that, you just get silver badges.
Friendship Badge shop
Gold badges
| Exchange Lineup | Gold badge cost | Cap |
|---|---|---|
  Lost Name |
600 | 1 |
 Lost Name Spirit × 10 (1st set) |
100 | 10 |
| Lost Name Spirit × 10 (2nd set) |
150 | 20 |
| Lost Name Spirit × 10 (3rd set) |
200 | 30 |
 Transcend Stone for Lost Name × 1 (1st set) |
100 | 94 |
| Transcend Stone for Lost Name × 1 (2nd set) |
200 | 88 |
Notes:
- Gold badge rewards do not reset.
- Initially only Lost Name is available, but after buying him, the spirit and transcend options are unlocked.
- Each set of spirits is unlocked after the previous set is exhausted. The same concept applies to the transcend stones.
Silver badges
| Exchange Lineup | Gold badge cost | Cap |
|---|---|---|
| Hell Genome Cube × 1 | 1,000 | No Cap |
 Pixie Underside Genome |
3,000 | 1 |
 Sword of Kusanagi 5★ |
100 | 20 / Month |
 Yata Mirror 5★ |
500 | 5 / Month |
 Yasaka Magatama 5★ |
200 | 5 / Month |
 Kasane Magatama |
3,000 | 2 / Month |
 Aether Crystal |
1,000 | 1 / Month |
 Skip Ticket (Sin) x20 |
3,000 | 1 / Month |
 Essence of Sin x160 |
2,000 | 2 / Month |
 Mitama Extract St x10 |
300 | 5 / Month |
 Mitama Extract Ma x10 |
300 | 5 / Month |
 Mitama Extract Vi x10 |
300 | 5 / Month |
 Mitama Extract Ag x10 |
300 | 5 / Month |
 Mitama Extract Lu x10 |
300 | 5 / Month |
 Blank Genome |
1,500 | 2 / Month |
 6★ Brand Cube |
500 | 10 / Month |
The Hell Genome Cube gives a random skill genome from a very large pool. A few of the skills are rare and exclusive:
| Genome | Notes |
|---|---|
 Fortunate park visitor |
Rare, exclusive |
 Trisagion Underside |
Rare, exclusive |
 Ice Age Underside |
Rare, exclusive |
 Struggle Slash Underside |
Rare, exclusive |
| Fire Slash Underside |
Rare, exclusive |
| Ice Slash Underside |
Rare, exclusive |
Misc
A Red 
Illuyanka was given out on Jan 20, 2025 with the exclusive skill Illuyanka Underside.
