Well, I guess I am lucky then.

I needed all 6 Helloween Mythicals, opened 5 souls in total:
1st - Musashi (Great, he was the one I wanted most)
2nd - Musashi (Eh????)
3rd - Icarus
4th - NOTB Eddie
5th - magus Hiero

After Musashi I longed for Count and Redan, but no luck this time. I would be able to get 2 more H. souls, but that would suck me dry on souls, so it is end for me.. Nice event, though.