I played vs Felix in doubles in two sets in tournament, and in a few singles friendlies. He probably wasn't trying his hardest, but the dairing from above while recovering was working like a charm.
Just a sneak peak at some of the things I've noticed:
Pro-Diddy
Kill setups:
Glide toss Bananas to d-smash
occurs primarily due to mistakes on the MK's part (tornadoing shield, mistaken move, mis-spaced move, etc.). Pretty much the only way Diddy gets a kill is from banana to d-smash/u-air/f-smash
Infinite
Other:
Over-b for mobility
Used when MK tornados (you can get away due to his low air mobility) or you need to get to bananas while he is in the air
Over-b when an opponent is dashing
If spaced correctly, this is a free over-b grab for the Diddy
Peanuts
When MK is on the ledge, simply throsing peanuts can do the trick
Throwing MK away
When you get a grab, throw MK off stage and set up your banana game
Hitting MK on landing
Diddy's u-air is normally pretty easily punished by a dair unless it is prefaced with a banana, but if MK lands on a platform above him it is a safe attempt at a u-air. If MK lands on the ground is it a free anything if the Diddy is set up properly; simply z-dropping a banana causes a trip, amongst more traditional punishes.
Insta-throwing
Used well, this can be very surprising to an opponent and can lead to multiple openings.
Throwing bananas up
MK can sometimes get a free banana, but when MK is air camping this is unpunishable. it's inevitably a winning scenario for Diddy.
Pro-MK
Kill setups:
Any attack off stage
-given multiple opportunities to hit Diddy when he is off stage
Edgehog
-very standard, simply grabbing the edge at the right time
Falling nair
-slow falled nair when Diddy is directly below the edge is a common kill move as it knocks him out of his barrels and makes him fall in a helpless state
Infinite
-the newly discovered infinite on Diddy out of a foostool if you have a banana
Other:
Sharking
-Diddy has no real answer to this. None. He can up+b spike you or down air spike you, but both are risky and easy to space against if you're careful.
U-air to up+b
Diddy relies on positioning to do well. U-air to up+b almost always takes him off stage, and this results in a ton of percentage added up... and mabye a KO.
Tornado as mobility
MK often finds himself falling into a trap; he can get out of this by simply tornadoing away in many circumstances; just don't press B to keep the tornado going and it ends fast enough for you. You can also land on the ledge for added saftey if he's far enough away.
You might say "DUH!" because you already knew all this. I did too, but what's important about all this is that it is confirmed at high level play, and if it isn't listed here I haven't been able to confirm it yet. I've still got a lot more videos to go through, but from what I've seen here's something reaaaally important for you to know when fighting Diddy:
He only kills you with banana to d-smash
Seriously, it's like 90% of this monkey's kills. The only time he gets this off is when you've made a mistake!
This means two things.
1. If you play near the edge of the stage, you'll die faster from the d-smash. That's bad. But if you play REALLY close to the edge, when he hits you with a banana you'll grab the ledge immediately and can't be down-smashed. That's good! If you're a stock up, you have no reason to ever leave this position since all of his attacks are now either damage dealing with no knockback (peanuts, banana) or easily punishable (any of his attacks). That's heavy information; Diddy literally can't kill you unless you mess up.
2. If you are behind and are approaching a higher %, you need to approach, right? Well, Diddy can't banana lock you to the end of the stage without two bananas. That means that if you appraoch him towards the center of the stage, it takes MUCH more % for him to kill you. This means on stages like FD and PS1 with relatively large stages they will more or less depend on you being near the sides of the stage. Stay near the center and you'll live to obscene percents.
I'll have a lot more to come. Diddy has some stuff too, of course, but it's seeming more in MK's control at the moment. Diddy is a strong reactionary character, he just doesn't leave much room for punishment.
Our current levle of knowledge is basically early MK vs. Snake. People thought Snake did an amazing job because his u-tilt killed at 80% (Diddy killing with glide toss bananas to d-smash at the edge for early kills) and his f-tilt did so much damage and near impossible to space yet Snake made you approach because of grenades (Diddy with nana in front, nana in hand, shooting grenades).
We learned to just avoid the u-tilt at all times because it's stupid not to, and we learned how to approach so that he can't reliably f-tilt us. It doesn't take too much effort to see the same when it happens to Diddy, and Diddy actually has less room to experiment than Snake. Diddy is a surprisingly limited character.