The Referral System (의뢰 시스템, uiloe siseutem)ⓘ is the only method to Enhance Transcended Characters and reinforce their stats.
It was introduced to the Korean game version with the Chapter 5 patch.
Referral Scrolls
The necessary materials for the system are the Referral Scrolls which can exclusively obtained through the new Daily Dungeon's Wednesday stage.
There are 3 different scroll ranks, and they give the experience points required to enhance the main character.
| Scroll | Rank | Usage | Gained Exp |
|---|---|---|---|
 |
C | Levels from 1 to 4 | 100 |
 |
B | Levels from 5 to 9 | 250 |
  |
A | Levels from 10 to 15 | 1125 |
Once a scroll is used, the played is transported to a dungeon where 1~4 waves of monsters must be fought. When the battle is over, the player is rewarded with experience points matching the rank of the scroll he used, and an additional reward (selected among shoes, tickets, golds or Jewels).
Superior rank scrolls can only be obtained by merging inferior rank scrolls.
- 3 C-rank scrolls to obtain a B-rank scroll
- 5 B-rank scrolls to obtain an A-rank scroll
Enhancement
| Level | Stats increase | Required Exp |
|---|---|---|
| 1 | 20% | 600 |
| 2 | 40% | 700 |
| 3 | 60% | 800 |
| 4 | 80% | 900 |
| 5 | 100% | 1000 |
| 6 | 140% | 1500 |
| 7 | 180% | 1750 |
| 8 | 220% | 2000 |
| 9 | 260% | 2250 |
| 10 | 300% | 2500 |
| 11 | 360% | 6750 |
| 12 | 420% | |
| 13 | 480% | |
| 14 | 540% | |
| 15 (Ultimate) | 600% |