Quoted from mfresh:

Arnie has been in 7 games:
Terminator 2 (Williams), Terminator 3 (Stern), and Last Action Hero (Data East). That’s three.
But he also appeared in a game with an unlicensed theme, viz SkitB’s Predator. So that’s four.
And he’s also been in the unreleased Data East Total Recall. So that’s five.
Arnie also features in two conversion kit games, as Pop Bumper Pete pointed out a while back: Nuova Bell Games’ World Defender, a conversion kit for Bally games, and Rowamet Indústria Eletrometalúrgica’s Conan, a conversion kit specifically for Bally’s Rolling Stones.
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Quoted from jonesjb:

I think we should only count official pins. And are we discussing being in the art or also if they provide vocals?

Quoted from modfather:

What about Joe Pesci. He is on LW3 and TFTC backglasses. Is there more ?