Jab -
Gotta love that delicious frame advantage. Jab to ftilt, jab to dash grab, jab to side B, jab to Fsmash if you're feeling brave, and let's not forget the jab to Down B. Sure, they're escapable, but who is expecting these kinds of followups? I use jab all the time on the runners like shiek and fox. The only way this move could possibly be better is if you could continuously jab by holding the button down like some other characters. That way you wouldn't have to have such a good sense of timing.
Ftilt -
These slightly slower f tilts lend themselves very well to being pivot moves, and this one has seems to have more than a couple active frames. Not a safe poke and doesn't have much killing power. You can angle the move, but there seems to be not much reason to do so.
Dtilt -
Can double hit at low percents for about 26% damage. Pretty safe to throw out in neutral, and hits lower than most of his moveset regarding opponents hanging on a ledge. Though Dair will likely get a kill when used on them, the D tilt has much less risk for its modest reward. The low knockback angle can kill opponents with bad recovery options. And the move seems to feature as much Knockback as F tilt, making it the more ideal attack when facing the opponent.
Utilt -
There are a lot of wrong ways to use this move, and not a high enough reward for landing it in the first place. It takes ages for this move to end, and you need to put your back to the opponent before using it. I've been able to link aerial Dash Slash into turnaround>uptilt, but that's about it for combos. I try not to use this ever. Not even for platform sharking.
Dash attack -
Pretty meh, but so are most dash attacks. Bowser's has a ton of reach, and with his very fast running speed in this game, it's a solid combination in the For Glory setting where opponents sit at the edge with projectile spam. I just prefer dash>side B or dash grab for punishing in a safer manner.
Fsmash -
This move is not bad at all, and feels great to pivot. It's primary use is fully charged after you successfuly break somebody's shield with our more awesome Down B. Try not to get too hungry making reads with this, Bowser's grounded Fortress and Dsmash have more active frames for catching people's rolls and spot dodges.
Dsmash -
Disjointed hitboxes, and multi hit. It has almost enough knockback for it to be a reliable kill move. Instead of more knockback, I'd wish for this attack to have a more horizontal knockback angle. Since Bowser's best kill options are already vertical kill moves.
Usmash -
A bit precise, but well worth the accuracy needed to land this. This is an upsmash that wins clashes with typical dairs, and has a pretty quick startup to boot. You can shark people from under platforms much safer than using the unwieldy up tilt.
Nair -
Ha, the wobbly legs. I can't find much use for this. It's a multihit move that only sometimes links together properly. It's generally unsafe to land with and must be full hopped in order to auto cancel. The hitboxes are not disjointed so the move is easily challenged from any angle. I guess you could juggle with this, but it's unlikely it will work with that auto cancel window.
Fair -
Very effective. The move will hit above, below, and anywhere in front of Bowser. It edgeguards, you can hit from a safe distance, and any Bowser knows that you can autocancel this out of a short hop. Make your opponent respect this, and you can force them to approach from the ground, where Bowser's options are more deadly.
Bair -
Lots of killing power with a horizontal angle. This one also has a generous autocancel window, but I mostly try to bait an airdodge on a falling target before using this to kill. I guess you can Rar this move to smack people on platforms, but Fair has a more generous range.
Dair -
How does this attack keep saving my ass? Bowser plummets to the ground extremely quickly, and if the early hitbox connects, the move spikes them rather than launching upwards. Use that aspect of the move near the ledge, and you can get a satisfying gimp. The move also features landing hitboxes to help keep Bowser protected from punishes, making it stand out from Bowser Bomb.
Uair -
The hitbox is much weaker than previous games, and only really includes bowser's head. It's functional, but not noteworthy, and it's annoying how such a subtly motion creates so much landing lag, or we could use this to poke from under a platform.
Neutral B 1, Fire Breath -
This move fits two very important applications. Making incoming projectiles disappear, and something you can potentially use to get on stage with after letting go of the ledge manually. The damage potential is low, but so is the potential for being punished. This move can protect your teammate as they recover in doubles since it functions as a decent wall.
Neutral B 2, Fire Shot -
Bad. The only good thing about this move is that it's a projectile that can't be clanked. It's slow to fire additional shots, and is not quick to act out of. If you fire these from a platform, you can have fun angling the move in order to have any effect on it. The low damage and knockback almost assures that any speedy character will punish you for this move. And you can't angle it far down enough to really disrupt recoveries.
It's interesting for specific MUs, but it has more wrong applications than right ones.
Neutral B 3, Fire Roar -
Besides being Bowser's manliest move, this is a risky version of breath. It dissipates extremely quickly, which cuts the higher damage potential. In addition, it takes a turtle's age to recharge. If we could use this almost as repeatedly as fire breath, it would make for a good alternative. The only application I can think of is if you're partnered with a character that can absorb it in doubles. But Fire breath could fulfill that just as well if you really cared.
Side B 1, Flying Slam -
Okay, suicide clause error aside, this is still an amazing move. The air version is lagless if you land, making for fun mixups from the ledge and on platforms. And if you're in a tumble state, but not in hitstun, you can use this just before landing to put Bowser in a neutral position. This application removes the need for teching, which is good since Bowser's tech rolls are garbage. This move is also the reason why I love battlefield, since you can get early (60-75%) kills on lighter characters if you manage to land on the top platform with some rage, which is entirely possible when grabbing from the ground. And the damage dealt is fantastic too. 18% is a good standout from our already great throws which deal 10-12.
Side B 2, Dash Slam -
The immeditate reason we want this, or dash slash, is because of waveslashing. Like normal Side B, the air version is lagless when landing. So even if this move whiffs, you can slide in for a jab, tilt, or another dash slam. It's a lot of fun, and allows Bowser to take charge of the situation and press advantages. This one in particular I think is great for getting up from the ledge with. However, I find this to be the least desirable choice for side B. You can still perform some of Flying slam's neat tricks with this and Slash, but the move itself is just the most underwhelming. At only 12% damage and no kill potential (besides bowsercide), I'd rather have the quicker flying slam as my command grab of choice.
Side B 3, Dash Slash -
Same as side B 2, but as an attack, rather than command grab. As such, most of what can be said about this is also said about the other move. However, this one can combo into attacks if you land after an aerial hit confirm. It knocks opponents airborne with low knockback. As long as you waveslashed correctly, it's often difficult to punish when shielded. Landing next to an opponent with a hitbox, then grab is a good mixup to cover for your loss of a command grab move. And when you do have a hit confirm, Bowser can followup with aerials, usmash and utilt, heck, maybe even slip bomb could followup from it.
Up B 1, Whirling Fortress -
This is a move that can't challenge many dairs and can't be B reversed. Make sure to utilize the boost correctly by pausing before mashing B to gain more height. Because of this, It's got better, more reliable recovery potential to make it stand out from the custom variants. A big reason to use this move is as an OoS option. However, it is nerfed from previous games and no longer features Frame 1-5 invulnerability. Still with a hitbox on Frame 6, it is his fastest grounded move, and by being an up special, definitely still good for OoS. In addition, if you're daring, you can use this to launch yourself at an opponent in the air or on a platform. When performed inside of them, the full damage potential is about 35%, but doesn't launch far.
Up B 2, Flying Fortress -
Bowser winds up before launching a set distance vertically. This move trades your excellent OoS option for a better recovery from vertical positions. Bowser winds up for 10 frames instead of six before launching upward. Your total recovery potential suffers greatly when you can't move horizontally at all. All you gain from this is the ability to edgeguard deeper with Fairs. Make sure your edgeguard connects, because you still can't B reverse this, meaning you won't ledge snap on the way back up. The damage potential is cut to about 4% and doesn't knock far enough to stage spike either. Also, for some reason, you cannot boost the height of this move like you can the other versions of Fortress. That's bizarre for the version that's all about gaining height.
UpB 3, Sliding Fortress -
Again, you're trading one of the best OoS options in the game for something mediocre in damage and knockback. This one takes 12 frames to wind up, that's double whirling Fortress. However, this one fulfills a better niche role than Flying fortress. When considering ledge options, you can use this to barrel through the opponent. Even if they shield this, you'll be on the other side of the stage when you land, making it difficult to punish. Bowser has a hard time on the ledge, without customs, but if customs are on, then you should use one of the custom side Bs for surprising the opponent instead.
This one gets a better rating because it isn't garbage for its intended purpose
Down B 1, Bowser Bomb -
Fantastic. It picks opponents up into the bomb itself and clocks a ton of damage. If the opponent successfully shields the rising hit, they'd better dodge roll, because they're shield will be broken if they sit there. I also love this for opponents considering their ledge options. I initiate it as soon as I see their character start moving. If their choice is ledge jump or simple getup, they can get clobbered very consistently. If they let go and jumped on stage, the rising hit will likely connect. If they chose dodge roll, Bowser can fall off the ledge and grab it, guaranteed. He didn't have this sure option in previous games because of the old ledgehog mechanics. The main drawback is of course how vulnerable you are after whiffing this move onstage. The custom variants have much less of an issue with this.
Down B 2, Turbulent Bomb -
This move has the furthest jump from the ground and the least amount of damage by far (about 9%, not counting the rising hit) The windbox will help ensure you're not punished on a whiff, but I question using this move in the first place when you consider its drop in damage and knockback. It also cannot break shields.
Down B 3, Slip Bomb -
This version of bomb lacks the rising hit, which means no linking out of a jab or punishing a laggy attack. To make up for it, this version, both from the air and ground, are much faster. The damage drop still keep this custom out of the common perception of viability. However, the knockback of this version seems to match, or is even stronger, than the Bowser Bomb. It also share's the standard bomb's ability to break shields, but good luck landing precisely on opponents without a rising hitbox. Trying to catch falling or generally airborne opponents seems to be the ideal purpose for this variant. As for the tripping effect, there's nothing to say. Bowser cannot follow up on it, even from a close range. That is, unless the opponent forgets that you have this version of the bomb and doesn't notice quick enough that they've been tripped. Maybe this will make for fun setups in doubles if your partner can followup, but that's really grasping. In case you're wondering, no, this trip effect does not go through shields, and deals virtually no shield damage/stun.
Grabs
Bowser's grab range and speed are above average since he's such a large character. His pivot grab has godlike range to where I often dash backward just so I can pivot grab my approaching opponent. If you've opted for Dash Slash over Flying slam, then your grabs become even more important.
Throws
Most characters have throws that are only average at best in Smash 4, but Bowser's are pretty good. Not Sonic level good, but still worth noting. They all deal at least 10% damage, and upthrow has some light combo potential. Bthrow and F throw can potentially kill if you've got some rage. All in all, he's got a bit of everything you'd want out of throws, and more.