Goat Simulator is the perfect word of mouth game. It's really bizarre and it fits perfectly into internet culture. I don't follow youtube personalities, but I could see this being the kind of game that does really well for them and in return well for the developers.
Also Sanctum is another tower defense game in a market overflowing with them. It's interesting and does coop well, but it didn't set the world on fire because it is honestly pretty average. I like it, but I understand why it isn't super popular.
> I don't follow youtube personalities, but I could see this being the kind of game that does really well for them
you are correct - especially the highly edited short-ish videos (ala, 10-15 minutes) of jump cuts to all the funny bits. Personally, i don't really like the game, as it seemed too gimmicky to play for more than a few minutes.
Also Sanctum is another tower defense game in a market overflowing with them. It's interesting and does coop well, but it didn't set the world on fire because it is honestly pretty average. I like it, but I understand why it isn't super popular.
Either way good for them on their success.