There once, was a giga which killed almost all my dinosaurs. And I lost most of my progress int hat world. But I didn't quit. I made a new base, grinder my life out, and then when I finally had enough materials, I made a gigantic platform full of refining forges, lit them all up, and locked it there with some behemoth gateways.

This is absolutely the most satisfying way to kill a giga, not too fast, but slow and painfully. But I guess you can't tame it the same way.