This has been said before but I'm writing it a tad differently than top comment, this is the method I use in solo play. These are a very easy tame if you have any type of fabricated weapon. Find an Argy that's away from the group, aggro it, then kill something else with a sidearm or assault rifle while it's attacking you, get near the dead body and when it attacks you (and hits the carapace) it'll get green health buff above it's head.

Knock it out and it's an insta tame.

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