“A stab in the back”in other languages

Same idea, different pictures

All three are blows you don't see coming. English stabs from behind, Italian gives a donkey's kick, il calcio dell'asino, and Persian strikes under the water, where nobody can see the blow.

The Italian one has a fable behind it: the old, dying lion is kicked by the donkey, the humblest animal, who would never have dared while the lion was strong.