3 people will be needed for this. You need two guys shooting the pursuing Wyvern whilst the other steals an egg and heads back to base. The Wyverns will only aggro on the egg carrier so the carrier must be on a fast flying dino. Fire into the pursuing Wyverns to make quick work and get the baby Wyvern you and your friends have always wanted. Happy hunting!
The best way to level up a Giga on Rag is to get a bunch of wyverns to follow you on your griffin/ptera, then dismount you’re flyer above the Giga, then get on your Giga and absolutely destroy them. This got my Giga 26 levels from 3 wyverns.