Quoted from Thanatos:
I still don't know all the rules, tonight on ball 1 I somehow got multiball without even getting up the ramp to pick a mode. I think it was all 7 of them because it was totally nuts. What the hell did I even do to even get it?
(Yeah, I'm pretty much a dummy with this machine. I can barely clear WHAT before my games are over.)
Sounds like you got house of 1000 corpses multiball - you knock down the drop target
And send 3 balls through the inner loop to get it.