Why is there a "yo" particle and not a "ga" particle in the phrase "Yūsha Satan yo kiseki o okose!" The phrase "Yūsha Satan yo kiseki o okose!" is translated as "Make a Miracle, Satan the Hero!" or "Valiant Mr. Satan, Work a Miracle!" . Why is there a yo particle after Satan and not a ga particle? Wasnt yo supposed to be an ending particle for emphasis? What does it mean here?

I believe this is the vocative , similar in meaning and usage to the English O. EDict mentions this meaning:

> (2) (after a noun) used when calling out to someone
>
> `` Lover, come back to me.

Japanese Wikipedia has this example from Latin:

> Quo vadis, domine? ``

You could translate the sentence as "O Satan the Hero, make a miracle happen!"