Necramech mods

[Mr.Zombie]

I was thinking to get necramech rage and necramech repair, I know that I can obtain them with something like 5% drop rate each from the enemy inside the big mouth puzzle, so I have to spam vaults, hope for the mouth to spawn, kill it, kill the guy inside it and hope for the mod to drop right?

[Nibbie]

Or trade for them with another player, yup. If you are going the 'get it yourself' way, I imagine loot frames (Nekros, Hydroid, Ivara, Khora) would be your best bet.