That would be "try, and".

Although the default rule for conjunctions joining predicates is that the comma is optional (by contrast, in most other contexts it is either mandatory or forbidden), there are a lot of circumstances where the comma becomes mandatory to avoid ambiguity or just because.

The two are not interchangeable though, as shown in the article. If someone asks you "Are you going to win?", you could say "I'll try to", but not "I'll try and".

Not sure this works in simple past though. Cf. Dune “They tried and failed? They tried and died”

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