This is automatic translation (from Korean) of 17.5.2021 update notice for Korean server (we will probably get same at our next maintenance):
 

Good morning. This is Cal Online.
The following is the update on 18.5.2021 (Tue).

 

1) Infinite Tower Boss Gauge 2nd Improvement

-The infinite tower boss gauge has been modified.

 

2) Infinite Tower Map Improvement

-The brightness of the infinite tower torch has been corrected.

 

3) Correction of the skill error of the swordsman

-Fixed a problem where the skill points of some skills were not decreased.

 

4) Shaman skill error correction (Rami user report)

-The phenomenon that the recovery amount of all recovery skills is low has been corrected.

 

5) Ancient Relic Shop Update

-For more information, please refer to the information page.

https://www.gameagit.com/kalonline/2105antique