There's a total of 8 companions in this image, but I actually have 9. My Kubrow (a dog-like pet) is in stasis (storage) because I can only have max of 1 pet at a time, currently Minthos.

Five of my companions have already been Max-leveled. My kubrow is still at lvl 20, I think. The 3 new sentinels: Diriga, Shade, Wyrm; are new ones that's why they're still unranked.

My mainly used companion is the Dethcube, mostly because that's the only one I had after Taxon. I preferred it over Taxon because this one actually shoots enemies and not jsut slow them down like what Taxon does.

Recently, I've been using Carrier more because it adds Ammo Capacity and converts ammo too, which is very useful in long missions and farming or trying to rank my weapons. Helios is also useful in scanning stuff in new planets for filling out my Codex.

I would very much like to get either a Carrier Prime or a Helios Prime but I can't afford them yet or they're still vaulted, so can't farm them.

Making other pet-type companions are really hard and expensive to do, so I'm keeping away from that for the meantime. Besides the Primed Sentinels, the only other sentinel I don't have is the Oxylus, which I could either buy with platinum or farm from Symaris.