Place it near the end of a failed attack sequence, after Enemy Spotted sets up the threat and before Okay Let's Go signals the next push, so the taunt answers the defeat instead of opening the clip.
About this sound
This is a short French voice taunt from Age of Empires II, lasting just over a second, in which a speaker delivers the line 'Même ma grand-mère peut faire mieux !' with mocking confidence. It feels funny and dismissive, like a playful insult aimed at a rival who has just made a weak move. It comes from the game's French taunt set, where it is listed as taunt 20.