Probably taming it isn't too hard. But too knock it out, you will need about 150 tranq arrows(crossbow) for lvl 1. For the trap (I didn't use metal gates because I was low lvl :3) Just go to the end of a river between 2 mountains, it won't drown (even a Rex just diving around and still alive). Giga will trapped there if it's fall to the little lake and flee, it can't even escape from a flat ground(after the lake) so just land with tape or quetz on a big iceberg and shoot it and that area probably safe(still must look around)and bring soothing balm(I use 1 with 3 raw meat and it's tamed :>) and don't forget the torpor, it will drop like the waterfall

That's all I guess and thanks for reading the tip

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