[Boom Beach] Matchmaking Analysis
The official explanation for Matchmaking
"You get new player opponents, referred to as Blackguard mercenaries in game, when exploring the map and as occasional invasions on your map. Your opponents are selected by a matchmaking process that attempts to give you the right level of challenge.
Your opponents are selected from players with a similar matchmaking score. Every time you get a new Mercenary base on your map, either through exploration or invasion, your matchmaking score increases. Using 'Find new opponent', Headquarters level, experience level or Victory Points have no effect on your matchmaking score.
Matchmaking score will gradually decrease over time if you have several player opponents on your map. Therefore, if you are regularly matched with opponents you cannot beat, you will eventually get easier opponents. Only active players' matchmaking score is adjusted down, so leaving the game for a long period of time won't result in the game getting too easy"
According to the official explanation, I feel the core of Matchmaking is that the less opponents on your map, the faster they refresh. So, when you are so sedulous to clear up your map, you become easier to be invaded (average refreshes the 10 to 20 opponents per day). However, if there are a mass of opponents on your map, refresh rate of opponents is not so fast (average refreshes the 1 to 5 opponents per day).
Moreover, if you clear up your field every day, your matching score will rapidly increase and never go down. Meanwhile, you will encounter increasingly powerful opponents. You may ask why can't match a low-level player, the official has said that your field decides the lower limit of your opponents' level, but not the upper limit. It means the opponents you encounter are more and more powerful until you can't defeat them. And last but not least, when you encounter a high-level player, that guy may find you too, because you two have a similar matchmaking score. So, it is common that level 30 player encountered level 50 player, 400 victory points player found 800 victory points player, etc. Yes, exactly, that is the consequence of over-diligent.
If you feel you can't defeat most of players on your map, then you should stop to invade and put your HQ in front of the beach.
NPC can't influence your matching score when they invade your map.