YOU MUST CONSTRUCT ADDITIONAL PYLONS.

This is a white card from Cards Against Humanity, and one of the few white cards that isn’t a noun. The card is itself a reference to StarCraft, in which if you attempt to create buildings or units without enough “pylons” while playing as the Protoss, an electronic voice irritatingly proclaims “You must construct additional pylons."

Yes, the full stop and capital letters are important. No, it wouldn’t work as well with an exclamation mark.

If you need to drop the capital letters for spam reasons, I would be miffed, but not offended.