【 HEROWARS MOBILE!! 】Which is more efficient? CSW coins? or Silver coins?

K'arkh is one of famous hero in Herowars!!
To get soul stones of K'arkh, which is more efficient? Using Booster? Or Silver Coins?

※Background
https://apps.apple.com/jp/app/hero-wars-fantasy-world/id1158967485

https://mobile.twitter.com/dx_unkoman3rd/status/1446714857525370883?t=R7KnkPaB8PVDrCh695NYBQ&s=06

※music
https://youtu.be/KI1Tt2EEWpY

#herowars #karkh #coins #shop #arbitrage #game