Entry location: Episode 4-3
To get this achievement, you have to merge two VSs together; yes, it's possible. It can only be done with two specific VSs: the GAN-34 (Blocky enclosed head, wing-like backpack) and the GAB-25M (the spider-like VS that can transform into a tank.) You need two human players for this. First, you must get the GAN-34 from the first area and keep it in good condition until the next area. Then, once you deactivate the first force field, go into the cave to the left of the generator you just used, and there is an unmanned GAB-25M. To merge them, have the GAB-25M in tank mode with the GAN-34 standing behind it. Have both players click in both thumbsticks and push them outward-if done right, the GAN-34 will hover and the back of the GAB-25M will open up. Then you should get a button prompt to Merge. Watch the short animation and the new GAN-34W Brocakti is ready to rock. Also, depending on which VS you used, you will get a new Nom de Guerre under "Play Style".