There is no grammatical subjunctive mood in Klingon.

I say that, but actually there is: -jaj forms a subjunctive mood. bInajtaHvIS qeylIS Daghomjaj May you encounter Kahless in your dreams. The encounter is strictly a wish, not something that actually happens, so it is an irrealis, and since this is indicated morphologically, it's pretty much a subjunctive mood.

There are also arguments to be made that certain other suffixes, like -nIS, also form subjunctive moods.

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SuStel
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