When something happens that is so improbable, it becomes unreasonable to assume that it’s legitimate. The phrase is a reference to Dream, a Minecraft speedrunner who attempted to write off his cheating as “just good luck”. Dream Luck is often used ironically to undermine the improbability of a given event.

Intelligence agency term for "psychological operation". A government or corporate-sponsored operation, usually taking the form of a "terrorist attack" or "crazed gunman on a spree", with the intent of panicking the public into demanding more police and laws inhibiting freedom. Psyops are usually carried out by drugging a civilian or group of civilians with aggression-promoting drugs, psyching them up, arming them, and sending them out to commit mayhem. Government-sponsored terrorism. See also blackshirts, conspiracy

Luck that's so bullshit, everyone will call you out on faking/cheating what you were doing, weather you were, or weren't faking/cheating it.

Luck that is unreasonably high. This phrase was created when the popular YouTuber Dream was found to possibly have tampered with in game drops for enderpearls.

A term used to describe an insanely high number of luck, a number so high that it is virtually improbable

Something with a 1 in 7.5 trillion chance of happening, or just something stupidly unlikely and improbable.

Luck as rare as Dream's. Just being really lucky I guess.
Luck with almost impossible probability.