I'm not going to lie, I am dying a little on the inside from both reading some of the messages and watching the Abadango videos in this thread.
I'm going to dump a huge wall of text here with a mixture of tech, general theory, strategies, matchup knowledge and stuff to avoid based on what I've experienced. I won't claim to be the best, but then again if Abadango is the best then wow we are coasting on opponents not knowing the matchup and need to step up our game (He gave away all 3 matches at least once but the opponents couldn't recognize it).
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First off, let's talk about SH Fair.
You can, in one SH, do a Fair and any aerial or special before you land. If you did the Fair while rising and DON'T fast fall, you will also have no landing lag.
I need to test when my training partner comes over next against characters with really good OoS options, but most characters cannot punish a well spaced Fair if you retreat with it and don't Fast Fall. This makes it a relatively safe poke option (Still punishable on read obviously) and opens a lot of mixups.
Say they try to roll, even if you whiffed your Fair, if you were retreating back then you can punish the roll with Nair before you land (For far rolls, you can use fruit, but depends on which one you have). Spotdodge gets punished on reaction with Fair/Nair/fruit/etc.
This means that at spaced Fair range, they have to respect a SH and either shield or pre-emptively throw out a move to beat Fair. This is where the mindgames start. If your opponent tends to opt for shield, you can just empty hop into a grab (This is probably one of the most reliable ways to get grabs for me). You can also FF into a trampoline to make them feel like shield is not a safe option. If you're feeling ballsy you can even Fair then go behind them and throw a Bair to catch an OoS option.
If they decide to throw out a move to punish a Fair and you didn't throw out a move, then you can easily punish.
One option at this range to mix them up and make them feel like they can't just wait it out in shield is to empty jump at this range and not move forward at all (AKA stay out of most character's range) then just fast fall a fruit charge. At that point you can just release whatever fruit you have as soon as you see the shield drop (Or if you can't react to that then either shield cancel or guess and throw it; you're safe regardless, but make sure to stay close to stop them from grabbing the fruit).
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Also one thing I'm seeing a lot in this thread is talk about how Pac rushes down, or how he deals with shields, or how he camps. I am getting flashbacks to the Injustice Joker forums where they assumed neutral game and traps were separate and 90% of them ended up playing the character completely wrong.
Pacman is not a zoner nor a rushdown; he is a setup/traps character. This character archetype is new to the series and Pacman actually differs from typical trap characters in fighting games in two important ways:
1) His traps can be used against him.
2) Unlike typical trap characters, Pacman is actually a well rounded character outside of his setups.
I do like the idea Dragontamer just presented about getting people off of the edge; this is the sort of thing we should be looking at. We need to limit our opponent's options whenever possible.
Take the ledge for example. At the ledge an opponent has 6 options:
-Ledge Jump
-Ledge Roll
-Ledge neutral getup
-Ledge getup attack
-Ledge drop
-Stay on the ledge
Worst case scenario, you want to be covering at least 3 of these options. With time to setup, you can and should cover all 6 at once (I already gave an example with hydrant, trampoline and bell a few weeks ago).
There are also actually a lot of ledge setups that look similar but cover different options based on how you do it. For example, in the bouncing hydrant setup Dragontamer just mentioned, there are a few ways out if you don't throw out an attack:
-Ledge roll
-A well timed Neutral Ledge wakeup
-An early ledge drop to avoid the hydrant
Now here's the thing: Based on what Pacman does, he can cover all of these options, just not all at the same time. Dsmash and Fsmash in either direction can cover the first two options, and a run off aerial or fruit can cover the 3rd. The opponent has to make a decision before he can check what you do otherwise his window to escape shrinks. This sets up a 33/33/33 guessing situation completely in our favor.
This was just an example, but these are the sort of things we need to mess with.
Here's another example that can be used in the neutral:
Grab your own apple. The best way I've found to do this is to throw it at a hydrant when the water is spraying. Once you have it in hand throwing it down makes it bounce in place, creating a wall.
If you can put this wall on one side of them and an active hydrant (I mean spraying water) on the other, their only options to avoid getting hit become to jump over the water, spotdodge the water, or shield the apple.
At this point throwing aerials at them is 100% safe (Unless they have an invul on startup move that makes them jump over the water like SL or Dolphin Slash) and punishes jumping and spotdodging.
A grab at this point beats spotdodging and shielding the fruit.
If you're riding the water charging a smash can beat the jump and the spotdodge, and is safe against shield.
If in this situation you somehow managed to set this up AND be behind the hydrant, then launching the hydrant behind the water is 100% safe, will punish anything except shield and will allow you to follow with anything against an opponent who did shield and probably shield poke if the hydrant didn't already do that.
These are just examples, and while I have landed both before in real matches, they are all situational.
That said, we are playing a trap character, so be creative and use whatever setup you can. Keep in mind that Apple and Melon when thrown up/down create a wall (In different ways, but still a wall) and that fruit gushing is a thing that can help a lot. In fact fruit gushing CAN be used to cover whiffed grabs. I've thrown bell upwards in front of an active hydrant, ran up and grabbed, then when they spotdodged and came to punish, they were hit by a gushed bell allowing me to punish.
I cannot stress this enough: Be creative and remember that we are playing a trap character. We should be trying to be tricky and set up stupidly broken traps. The goal should be to make the opponent feel like they have no options and that anyone who doesn't know the matchup should be completely free. Use slants. Use water. Use platforms. All of these things affect our ability to set up traps.
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On a related note... Key is not the only fruit. In fact I would say it's not even the best fruit unless you are really, REALLY needing to kill an opponent. It is strong, sure, and it moves fast, but it has less utility than any other fruit and picking it up is nigh impossible unless the opponent grabs it first.
Speaking of grabbing fruits, having the fruits in your hand is much MUCH better than having it charged but not out. For one your fruits get a lot more versatility in that you can Z-drop them and jump cancel glide toss them (Very important!), but they also act differently when thrown up and down than they normally do. This makes them all much more useful for setting up traps, punishing OoS (More on this later), and edge guarding.
For example, throwing a melon downwards/upwards in front of the ledge will prevent an opponent from grabbing the ledge for the melon's duration.
Now picking up the fruits in the first place can be a challenge. Here's some ways I've found to pick these up easily:
-Cherry: Just follow it, water gush it back to yourself, or throw it at a slant.
-Strawberry: Same as the above.
-Orange: I honestly don't have a clue on how to grab this one easily. Maybe with a slant? I don't remember if that works for Orange.
-Apple: Water gush it. Slants don't work, although it does get interesting properties on slants.
-Melon: Following it works, but the opponent can easily grab it away from you. Slants are another way, or hitting your hydrant then catching it.
-Galaga Ship: Follow it or throw it at a platform.
-Bell: Follow it. It can be caught through Hydrant gushing, but the water gushed bell is so good it's sometimes worth leaving it out.
-Key: I don't know. Have the opponent catch it, throw it back, then catch it yourself?
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Speaking of fruits... DON'T LET THE OPPONENT GRAB YOUR FRUIT (ESPECIALLY BELL)! This is very, VERY important, especially if the character in question has projectiles of any kind.
Once an opponent has your fruit, if they know the matchup then they know they have literally nothing to fear from you at a range anymore. Hydrant launches are reactable, so they can just wait and shield, or even worse, if they have a decent projectile, shoot it right when you are about to use a move that launches.
This forces Pacman to approach, and against some characters that can be very bad, or in some cases borderline impossible.
If the other player has the life lead, then they can literally just run away from you for the rest of the match, especially if they are someone like Sonic.
I had my training partner, air camp me as Kirby with my bell on the Kongo Jungle 64 stage the other day. After 4 minutes I killed myself and ended the match so we could play a less stupid match.
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Now as for the reason I said to ESPECIALLY not let the opponent grab bell is the same reason as why I said having a fruit in hand helps with OoS game.
I'm sure many of you know that the fastest ways to drop shield are through either grabbing, jumping or jump canceled actions like UpB (By the way, UpB OoS is godlike) or Usmash.
However, there is one more jump canceled action: The jump canceled item toss. This allows you to drop shield as fast as the jumping or grabbing and throw the item in your hand, and item tosses are already fast. When the item in question is bell, this allows the person holding the bell to punish nearly anything with a jump canceled glide tossed stun which can combo into the kill move of your choice.
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Another piece of random tech one of the guys at my local scene who dabbled in Pacman gave me:
When the opponent dies, throw a trampoline right where they will respawn.
This will kill their invulnerability time and can even sometimes lead to a punish as they have no choice but to hit that as soon as they come back.
If they got star KO'd/screen splatted, make it either red or set it to the highest bounce, depending on the stage (Example, free fall is less useful on a stage like BF since they won't fall far, but on Skyworld it can eat the entire invulnerability time and give you a punish.).
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I feel like I'm forgetting some important things, but oh well. I just wrote out 5 full pages, so I'm done for tonight.
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EDIT:
Wait, actually I forgot some anti-diddy tech:
If Diddy throws out a banana, walk over to it and lay a trampoline right on top of it. It prevents Diddy from grabbing it while simultaneously preventing him from pulling one out, essentially taking it out of the game.