i dont know because jimbothy on yt claims that you can get a Nuke by going 25-0 and that it omly works in free for all first but then is open to every game mode after. link is below
the only hidden killstreak I know of is when the enemy calls in a uva/cuav and it disappears into the clouds when I try to shoot it down.
It's a troll, there isn't any hidden killstreaks discovered yet. So there could be some, start looking.
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