Both damn.dog and idiots.win have huge peaks and valleys in traffic. They've both seen days of more than half a million games played in a 24 hour period, and they can both flatline. Although, damn.dog is the more popular game, so it's low point is probably around 1,500 sessions, idiots.win can get down to about 200 sessions.
It's worth mentioning that basically ALL of this traffic, in both cases, is direct. There's a couple subreddits that must be bringing some people in, but basically all of the people playing the game are doing so because they typed my dumb url into their browser. Which is nice, but I'm guessing that means most of this traffic is still based on YouTube.... Mixed emotions on that fact.
ACTUALLY, while we're talking about it, does anyone know if PewDiePie (or someone similar) did a video on idiots.win on February 8th? There's a huge spike there, and it can't be explained by the videos I'm seeing in doing a cursory search.