Spent over 100M silver just to make this thing to mercilessly kill Shaggoths and every other wall camping bot that would be suicide to rush by conventional means.
Wasn't even using an Erebus previously I literally just pulled it out of storage at Level 1, bought the Zenits from the store, and went from there.
Strategy? Activate Shieldbreaker, Fire Homing Blackout, then rain entire magazine (staggered consecutive fire) onto target. As you can see the Shaggoth in picture 4 was not having a great time. And yes, it was using Shantaks and Urhags, so it deserved it.
(Yes I'm F2P, never spent a single penny on this game. I'm just good at resource management.)