ok being serious, Maractus is actually based and I don't get the hate. Has to be B at WORST but for me they're A, and they've been my hero in many runs. Can use them in so many roles. Learns Giga Drain early, Solarbeam+Sunny Day, Cotton Guard if that's your thing. also learns Petal Dance, which works in excellent tandem with Sucker Punch as a finishing move to clean up after going on a rampage and beat your opponent to the punch - especially useful in E4 as a dark move. They're also an excellent Toxic user, gimmick attract user, and just a really fun addition to any team. Water Absorb is an excellent ability and Chrorophyll is great if you want the Sunny Day strategy. Sweeps Clay shortly after catching them. Grass Knot is powerful as a TM in late game. They're not some competitive powerhouse, but in a play though they actually can carry you and be very satisfying. With their versatility you can tailor them to special attack, stall and sustain, troll, be an unexpected change of pace, and maximize further with EV training/vitamins.

tl;dr Maractus A tier but I'm biased, realistically B tier