Tree of Savior Forum

States success rates for Seal Enhancement are inaccurate

Please fill in as much as you can :

Date and Time(Please, specify the timezone) : 11/19/2023, 6:50pm CST

Server Name: Klaipeda

Team Name: Diggity

Character Name: Ashyliaes

Bug Description :
(letting us know what you were doing before, during, and after the bug happened will help us a lot)

Steps to reproduce the issue :

  1. Take as many +1 boruta seal as possible
  2. go to Blacksmith Teliavelis
  3. Enhance as many double sets of +1 seals as possible without using magic stones
  4. Listed success rate is 50%, it will quickly become quite obvious that this is not accurate.

This is a very concerning bug for me, since as the game has a cash shop it can arguably be construed as online gambling, and it is illegal in many jurisdictions to display false odds at e-casinos.

Displaying accurate odds would surely solve the issue for the community.

Screenshots / Video :
(attach screenshots or videos regarding the bug)

Game Control Mode (Keyboard/Joypad/Mouse) : Keyboard


  • CPU : Ryzen 7 1700x
  • RAM : 32 gb DDR4 @3200mhz
  • Graphics Card : GTX 1080
  • Mainboard : BIOSTAR X370GT3
  • Storage : ADATA SP550
  • OS : Windows 10 Pro
  • Internet Connection : TMobile 5G
  • Country, Region : USA

Take 99% of the games and you’ll see they use a biased RNG. Mainly they use a non-gaussian one leading to lots of dispersion in the numbers they generate. The issue with that is that you can succeed upgrading a piece of equipment with 10% chance ten times in a row and they fail 100 times in a row. Some games will fix this with a “pity” system: for the previous example, they guarantee you get 100% chance of success after 10 tries (or usually a bit more) so you don’t waste high amounts of materials on “unlucky” streaks.

ToS RNG is actually really bad in this matter. Recently I’ve spent an insane amount of mats just upgrading eight pieces of level 500 equipment from +10 to +11 where the chance of success is 52% with 3x enhance aids. Instead of average 16 tries I think it took me 60+ or so, failing 8-10 times on each piece. Then a +20 piece upgraded to +21 instantly. Go figure…