Id recommend take metal dino gate's and luring the giga inside them. That way you don't have to kite it around. Put a large beartrap in the center of the dino gate's that way when giga is lured inside it traps him long enough for you to run around and put up fourth gate.
We were using a high damage crossbow but switched to darts and got it out in about 90. Tamed it whilst being killed by trolls who then followed us and wiped our base haha you win some you loose some i guess