YOU SAID:
X was joined by Y for the encore
INTO JAPANESE
アンコールのためにXにYが加わりました
BACK INTO ENGLISH
Y added to X for encore
INTO JAPANESE
アンコール用にYをXに追加
BACK INTO ENGLISH
Add Y to X for encore
INTO JAPANESE
アンコール用にYをXに追加
BACK INTO ENGLISH
Add Y to X for encore
Well done, yes, well done!