Just get a crossbow with 40 toxicant arrows, 4000 cinidaria venom, soothing balm (if console or pc use prime meat because they like it more so taming will be quicker) and 500 meat. Then shoot it down and give the balm, give it meat and if you use the balm that you get from hunt raptor it will take 3 meat pieces. This will pretty much work for any giga with 80,000 health or below (I got a 83k in my experience).

Hope this helps!

-GitezGood

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