"He can only use it once"
He can use it again, it's just not something he can spam continuously. He needs time to build it up beforehand like he did the first time.
Just take the L man
🚨📈 OFFICIAL: Black Clover Season 2 Episode 5 has officially smashed past 80,500 LIKES on Crunchyroll in 16 hours!
It is now the FASTEST-LIKED episode of Black Clover!