冥福を祈る
May you enjoy every happiness!
I wish you luck.
ご多幸を祈って.
with best wishes=with every good wish
I wish you every happiness.
I wish for your great happiness.
I wish you every happiness (and prosperity).
We pray that his soul may rest in peace.
May his glorious reign last for ever!
With best wishes.
幸運を祈るよ。