The game "slurpy" behaves differently in VICE and on real hardware, and the reason seems to be the initial TOD alarm time:
On real hardware, when the player takes too long to finish a level, rocks start falling from the ceiling.
In VICE, those rocks start falling right away at the start of the level. POKEing the TOD alarm time of CIA 2 to 9:09:09.9 before running the game inhibits this behaviour.
Our guess (!) is that the game relies on the default TOD alarm time, and that a real CIA chip does not use the value 0:00:00.0 (as used by VICE).
This bug was found by Roboklotz 4711 and Cold Sewers, I'm merely the messenger...
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