They (admins) recently started a couple of new German language subreddits, that were 1-to-1 translations of existing successful subreddits, like r/showerthoughts and r/explainlikeimfive. They very clearly created fake accounts that then posted badly translated copies of existing posts from those originals onto the new subreddits. Then after that they sent unsolicited private messages to users subscribed to certain organic German language subreddits (like r/de) inviting people to those new subreddits.

The r/de subreddit is still in blackout, so I can't really provide a working source right now, but once that ends, you can check it out here: https://reddit.com/r/de/comments/13orxh0/milde_interessant_r...