Let me begin by saying that this is in no way new information - indeed many of you might already be doing this. What I'm about to detail in this post is a short guide to earning Powerplay Merits by undermining opposing Powers as an alternative to grinding Expansion missions into the tens of thousands %.
Why grinding Expansion goals is bad
Right now we have 3 Expansion goals going, all of which are at several thousand % above the required threshold. These will be achieved no matter what, there is simply no way for the opposition to undermine our efforts at this point. Now, the reason most CMDRs are farming these goals is because they want Merits, not because they wish to help the cause. It started that way, sure, but now it's just the go-to method of gaining Merits through combat.
The problem lies in the fact that President Hudson's Faction is combat focused - in fact, it's the only one out of the 10 Powers with all 3 types of PP actions listed as Combat in the Ethos section. (Even the pirates have just 2 out of 3!). This undoubtedly led many CMDRs to pledge to Hudson in the hope that they can participate in Powerplay while doing what they love best - fighting and killing. However, if we keep this up and only focus on expansions instead of fortifying and consolidating our current holdings, we will lose in the long run.
So what do you do instead? You undermine the other Powers, of course! Granted, this is not the best solution - that would be to pick up a space truck and start shipping supplies in order to fortify our existing systems, and only then move on to undermining, but we're here for combat, right? So at least let's do something moderately helpful to our beloved Federation, instead of grinding Military Strikes for no gain at all.
Undermine the opposition for fun and profits
First we have to find a system that needs messing with. Either go to the Galaxy Map, switch to Powerplay view, and then tick the "Control Systems" option down at the bottom or check the Powerplay menu and browse through the other Factions, checking their Control tab. Either way you do it, look for Control Systems that have less than 100% of the Undermining goal achieved.
Once you find a suitable target, plot a course and head on over there. This may take a while, since most not-yet-undermined opposing systems are deep behind enemy lines, but it's well worth the trip. Once you get to the target enemy Control System, fly around in Supercruise and look for ships with a particular name: * Imperial Supply (Arrisa) * Imperial Support (Patreus) * Private Security (Torval) * Alliance Bureaucrat (Mahon) * Campaign (Aisling) * Sirius Transports (Li Yong-Rui) * Crew Transports (Archon Delaine) * Reform (Pranav Antal)
There are quite a lot of these types of ships spawning constantly in each enemy Control System. Just wait around a bit and chase them while they fly from the sun to a station. Now that you have the targets in sight, you need to interdict them and drop them out of Supercruise. Most of these ships are freighters, so it's easy. The last step is simple: blow them up. You will get a bounty for murder, but it's well worth it. After the kill, check your Transactions tab and see 15 shiny new Merits as a your well earned reward. Yes, 15 Merits per kill while undermining.
Wrap-up
It's fun, it's thrilling (you are behind enemy lines, after all), it often leads to PvP, and it's very rewarding at 15 Merits per kill compared to the 1 Merit per kill you get while doing the expansion Military Strike missions. Not to mention that once you get the hang of it, it goes very quickly. I made 350 Merits in a few scant hours, playing on and off again while cooking lunch and reading the subreddit. And let me put it this way: you only need to kill 100 of these targets to get to Rating 4 with the Faction - That's 5 Million credits for 100 kills, plus the rest of the benefits from loyalty.
So get going, CMRDs! Wreck some havoc behind enemy lines and make them work for their territory.
-CMDR Vilverum Fae