Splatoon for me. It just felt right, especially after seeing (and playing some) so many shooters that felt or looked too similar to each other. While I enjoyed a few like CoD 4, Black Ops, and Battlefield Bad Company 2, I mostly played the campaigns Since I felt intimidated by the multiplayer stories. Titanfall might look fun but I didn't care too much about it since it didn't look like it differentiated too much from others outside of the Titans, which looked cool. Same with Evolve, Battlefield, CoD, etc. Granted I'm not great with shooters so I guess the games out there didn't help me get invested.
With Splatoon, though, I felt welcomed. The design sparked positive vibes and the world was interesting. And the gameplay was and still is so addicting. The music is awesome to listen to, even songs from Callie and Marie. Some didn't like lack of voice chat, but I didn't care since I didn't play online with friends and I was able to communicate through the game pad, seeing how the territory was progressing with ink and where my teammates are. The campaign was fun and underrated. I felt like I could really play online in Splatoon because I didn't have to rely on killing in order to succeed. Covering territory with turf could be all I'll do and it'll be more than beneficial. I remember getting no kills but having my team won anyway because I helped cover turf. Plus the community, the updates, and the Splatfests kept me engaged overtime even if I was a little late to the Splatoon party. And to see where it's at now with Callie and Marie concerts, various merchandise, the success story it was, especially in Japan where home consoles are not where they used to be, and it's highly anticipated sequel showing even greater potential, I like where Splatoon is going.