Quoted from manadams:So is the apron lock a first for pinball or has this been done before on another game?
GNR CE has the Coma Lock. There's an old EM - Space Station? that sort of locked the balls into a saucer at the back of th flippers, then kicked them out, but not a ball lock for multiball as such. There's probably more - designers were willing to take risks back in the day. I'm thinking we're starting to see more of it now that there is some competition and manufacturers are looking to differentiate themselves (from Stern mostly).
Edit: not Space Station - Space something. Fun game with a Thunderbirds style moving target in the middle.
Edit Edit: Space Mission :
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