He spent a lot of money on microtransactions in this game.
Tips
usage
In Chinese internet slang, 氪 (from 氪金 kèjīn, 'krypton gold') means to spend real money on in-game purchases. 氪金玩家 (kèjīn wánjiā) refers to a 'pay-to-win player.' This usage comes from a Japanese mobile game.
culture
The slang sense is extremely common among young Chinese gamers. 微氪 (wēikè) means 'light spender,' 重氪 (zhòngkè) means 'heavy spender,' and 零氪 (língkè) means 'free-to-play.'
气 wraps the upper-right corner — the gas radical that flags this character as a noble gas. Modern Chinese chemistry uses this header systematically: 氢氦氧氮氖, every gaseous element wears 气.
克 supplies the sound kè directly. This is a modern coined character following the regular pattern: gas radical + phonetic = element name. The phonetic was chosen to approximate the kr- sound of krypton.