Crossovers

Firefly/Avengers

In Two Straight Lines in Rain or Shine by sienamystic
Utterly perfect crossover where Natasha is another product of the hands of blue, and River convinces Mal to help save her.

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The Losers/Avengers

one for the road by beardsley
Silly little white girl, thinking all her training and all her skills would be enough to get her a seat at the grownups' table. Aisha loved proving her wrong, back in Sarajevo. She loved proving her wrong with her forearm against Red's throat, Red's gun under Aisha's chin and her thighs clamped so tight around Aisha's waist Aisha thought she might actually have to kill her to get away. She didn't. She's glad. This way, they get to do it again. Sharp, hot Aisha/Natasha.

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Criminal Minds/Avengers

there is no hunting like the hunting of man by jedibuttercup
Highly enjoyable story in which the BAU profiles various Avengers.

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Mission Impossible/Avengers

What's Wrong With Spiders? by coralysendria
Five times Natasha worked with Ethan Hunt and the IMF. I enjoyed this a lot.

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