Can anyone give me some information on the Side-B Mechanics? I've done a search here but couldn't find anything.
EDIT: Actually a moveset write up for the specials would be great. Heard you can mash Up-B in some instances. Thanks!
Flying Slam is a command grab that's got frame 8 startup and frame 17 startup from the air. And half to most of Bowser's character-specific tech relates to this move in some way. The air version has no landing lag state so the move "auto cancels" whether the grab had become active or not. No other special move has this property in Smash 4. Bowser's auto cancel lag or "hard landing" lag is 6 frames, so when we say the move is lagless, we really mean it's as lagless as autocancelling an aerial. If you've heard of
A-landing, Bowser can do that with Side B, but it works on any frame, not just the first three or so, and it's a great landing mixup when it looks like Bowser will tech the ground, but is suddenly standing upright with his shield, or performing jab. Using Aerial Side B as an attack is also interesting because the typical response to an airborne target approaching you is to shield - after all, they can't grab from the air. Not only does an air grab deal with shields, it also deals with dodges. If the other player spot dodges or rolls to escape air side B, Bowser only suffers 6 frames of landing lag while they're stuck in a long animation.
When you successfully grab a target, both Bowser and the victim can influence the direction with the control stick pressing left or right. How much control each player has is dependent on the difference between their current damage.
This thread provides some data. Bowser generally has more control than the victim, and a slight edge if he's trying to move in the direction he's facing. This priority of influence is great because it's unlikely the victim will take you over the edge when you don't want to, and also lets you precisely aim to land on platforms for a greater likelihood of a vertical kill. When you take a victim over the edge to kill them (officially dubbed "Bowsercide"), it doesn't behave 100% consistently. Sometimes both characters die on the same frame, which will lead to a sudden death if both were on the last stock. The game itself does not ever rule Bowser the victor unless he had one more stock than the opponent, so refer to your tournament's ruleset on what to do about a sudden death, or if there's a suicide clause that mentions Bowsercide. The other possibility is that the victim is released at the bottom blastzone as Bowser is killed. This is an issue because the victim is in a neutral falling state, and may have a good enough recovery to return to the ledge. In a non-customs environment on Battlefield (which has a very high ledge from the bottom blastzone),
16 characters can make it back to the ledge if they know what to do. As for what stages consistently release the opponent, there's no confirmed consensus, as all our lists have been refuted at least once when stress testing possibilities. In general, I've never seen a double KO on Battlefield, Town and City, and Lylat Cruise, and omega stages don't have the same ruling as normal FD - about half release the victim while the other half have a double KO.
That's generally it for Side B as it is currently. Fire Breath has no important tech. Just know that when you blast the move over the edge or into the air, a larger portion of the move becomes a damaging windbox that you may or may not want. It's a commital attack to use in 1v1, generally only left to certain matchups where the victim has extreme difficulty getting over the flames safely, like Doctor Mario, Ganondorf, Roy, etc. It's also consistent in hitting opponents trying to grab the ledge for free damage, and it's vital for the Bowser jr matchup since you can instant kill him if he used Up B to get to the ledge.
Bowser Bomb is also mundane. It is a frame 11 vertical kill move with great range, but it can occasionally knock the opponent too far if they are randomly holding away from Bowser, or are playing as jigglypuff. The closer you are with the initial hitbox, and the less rage Bowser has, the better. It used to be the premiere hard punish until Bowser got a combo throw. Now with dash grab, Bowser can deal even more damage than Bomb and get earlier kills. Bowser can grab the ledge when falling, just make sure you're not still holding down as you pass it. It's a good idea to use this to get down from the air to the ledge in a way that they can't challenge. Counters are a good answer to that, but I've yet to see an opponent think to use that in time. Landing onstage with Bowser Bomb will incur 55 frames of landing lag which is riskier than even Dair. However, it will break shields.
Whirling Fortress is a very technical move. From the ground it's Bowser's fastest OoS option that easily deals with crossups. It has lost some perks from previous games, like allowing Bowser to fall off a ledge and grab it as a way to cut the move's long endlag. And it also no longer has 5 frames of invulnerability. Since the move has 24 active hit frames, that's enough to consistently hit all ledge options from the opponent.
You can learn more here. Air Fortress is a pretty good recovery move. By learning how to
fortress boost, Bowser gains more distance and height. Allowing you to edgeguard deeper, approach the ledge from less linear angles, and save your double jump as a means of getting past your opponent's edgeguards. Air Fortress grabs the ledge as early as frame 8 both in front and behind, which is great as it allows you to get liberal with offstage aerials if that's how you prefer to edgeguard. It's not so good for recovering on to the stage rather than grabbing the ledge. The move has 50 frames of special landing lag rather than the standard 30. There's a hitbox on every frame of air fortress, but it's not very disjointed to the sides or above Bowser. Combined with Fortress' slow movement speed, it's easy to hit Bowser with a variety of low priority attacks. Also landing all hitboxes of Air fortress will deal over 30% damage. Which is insane, but not considered viable with how the move clearly wasn't designed to be used as a deliberate attack.