Easy way to kill a giga is with the following items ascendant compound bow 150 metal arrows 4 c4 10 rockets and the basic trap and 45 simple fab pistol bullets and a flyer lead the big guy in the trap on a argy or griffin place a c4 at end of trap when giga is in bear trap close off trap and throw giga with c4 bullets explosive then shoot arrows in head on mobile if you do it for quest you'll get a titan saddle be careful it weight 200 kg