Splatoon 2
Leave it to Nintendo to take a simple concept like squad-based shooters and turn it into something both unique and fun. SPlatoon 2 is one of those games that I really wish every person gets a chance to play.
It's super colorful and weird. Your character is a "squid kid" armed with a super soaker full of paint. In Splatoon's main game mode, Turf War, the goal is to splatter this paint on every single wall, floor, ramp, and player you can reach. The maps are symmetrical, with one team on each end fighting towards the center to cover as much of the map with their team's paint color as possible before time is up. Blasting other players with pain will splat them back to the spawn point.
There are different types of weapons you can equip, ranging from the basic automatic splat gun, the "duelies" duel sub-machine guns, a paint bucker, a paint roller, a paint brush, and a sniper rifle. Things like the bucket or roller are great for covering large areas with paint, but suck offensively. Alternatively, the sniper as really good at picking off people or putting plaint in hard to reach areas, but is slow and hard to cover areas with. Each one has its pros and cons.
Besides your main weapon, you also have a sub-weapon (like grenades or sprinklers) and an ultimate move that charges up over time. You can also equip different pieces of gear to your character to give them advantages, like increased speed or tougher armor.
There's a few other modes besides Turf War that involve stuff like pushing a payload, but none are as fun.
My biggest gripe is with Nintendo's archaic stance on online communication. There's absolutely no voice chat without a convoluted setup, and even then it's only private channels. In a squad-based game like this, communication is key and your there's like an 80% chance your team is gonna be idiots. It's also not possible to coordinate weapons, as you can't see what weapons your team is using so you occasionally get a team of Hanzo-wannabes.
In addition to multi-player, there's a full fledged single-player campaign and a horde mode. The single-player is pretty short and makes you try out a variety of weapons, so it's worth playing. The horde mode is a lot of fun, and has unique bosses and weapons.
Every time you play the game it's different, since the maps rotate in and out. A few times a year they held "Splat Fest" that had special versions of the maps. I gotta mention the music, the soundtrack is off-the-walls bonkers and all the lyrics are in this weird "squid language." Just listen to this catchy shit: https://www.youtube.com/watch?v=4CeO4S0wON0
Saki got super super into this game, and played it way more than me. It's a must play if you own a Switch. I really wish this game was for PS4 or something so everyone could enjoy it.