Wonders never cease... Erebus is being shipped, which means he might make it in time. I won't have much time to test him on the table, but suddenly my Terminus list seems viable. Erebus allows for some interesting new plays with Terminus.
As a bodyguard for Terminus they don't come much better than this. Erebus is defense fourteen, armor eighteen, and has the Poltergeist ability. This means that missing him means the end of most models attacks on him, and that infantry will have a hard time hitting and damaging him. This is the helljack that was meant to stand in front of Terminus and go "Thou shall not pass". Erebus will probably pay for that assignment with his life, but so did my Leviathans, and with Erebus one bad roll can spell disaster for an opponent.
Secondly he has Overtake, and Terminus has Ravager. This means that we now have access to eSlaughterborn, though he needs some tightly packed infantry to make it work. The problem was always getting Gerlack Slaughterborn across the table, but this time we've got it in a defense fourteen helljack package, though his potential for kills is entirely dependent on opponent placement. I don't think an Erebus killing spree will be a common sight, but the potential is worth something as well.
Overtake also allows for some Molik Karn like action. Assign Erebus three Focus, have the Skarlock pop Ravager on him, and have Tremulus put on puppet master. As long as there are more infantry models in range, Erebus will keep going towards a caster (if the chain stops he has a second claw to initiate a new chain of berserk attacks, and two focus as well). This means that an opponent cannot allow himself to saturate the area around his caster with infantry, but he also can't leave it open (or Terminus has a place to land).
Erebus gives Terminus something he's been lacking for a while, which is a viable assassination threat beyond himself. Erebus is also the king of getting in the way and messing up charges and combinations, and he punishes bad dice as well. If all this actually works in real games remains to be seen, but I'm looking forward to trying it.