The way I typically handle these things is to put a few bullet points to an idea then see if any of those bullets trigger through “play to find out” at the table. If they trigger, I would take note then flesh it out further between sessions.
In this case, I would start with the fact that this is some type of Electroplasmic Entity that is non-human with a fundamentally non-human view of the world (perhaps a Horror, page 252 in the rule book?). Therefor, I would say it came into Doskvol with no real intent to interact with humans:
- ignores people
- seeks to interact with Plasm
- open/close Electroplasmic gates
- destroy lighting towers (because they are an unnatural channeling of Plasm?)
- damage Leviathan Hunter Ships (because they harm the Plasmic balance?)
So it would be going after the towers or ships. Not the people. The way people could be involved:
- Neighborhood citizen Factions could be agitated by neighborhoods going dark.
- Blue coats or Inspectors are ordered to deal with the situation.
- Do the Sparkwrights, Spirit Wardens or Leviathan Hunters get involved?
Bottom line. Decide what its Motivations are. It could actually be more or less dangerous depending on what it is actually doing. The “interacts with Plasm” bullet could open up a huge possibility of motivations, actions and fiction.
Those are just some thoughts and I may have strayed from what you were wanting. If it is a minion for a cult or a powerful mastermind be careful not to start giving it human motivations (at least if you really want to keep it non-human).