The opening — Toadstool is kidnapped, so Mario Storms The Castle and fights his way to Bowser in under five minutes. For that matter, the duel with Bowser is great in spite of its ease, Mario and Bowser battling atop chandeliers in Bowser's throne room, Toadstool strung up between them. And Mario wins by knocking out the Chain Chomp holding up Bowser's chandelier, sending him to a Disney Villain Death. The entire set piece genuinely feels like a final boss in any other Mario game.
On top of that, just to show this isn't like any other Mario game before, as soon as Bowser is defeated, a giant sword with eyes suddenly descends from the heavens and stabs into Bowser's Castle, sending Mario, Toadstool and Bowser across the kingdom. To reiterate: the game starts with the usual Mario vs. Bowser skirmish, and then introduces its main villains after Mario has seemingly won.
Most of the boss fights with the members of Smithy's gang, due to their challenge level, awesome designs, and the fantastic boss music.
Mack the Knife, a Wake-Up Call Boss for the rest of the game after the Hammer Brothers and Croco. He attacks with four of his Shysters, can use the group-hitting Flame Wall, and jump and stab you for one of his other attacks.
Bowyer is one of the few Puzzle Bosses in the game, as he will lock your A, X, or Y commands, preventing usage of attacks, items, or special attacks. Beating him requires you to not only be strong, but smart.
Yaridovich may be That One Boss, but damn if he doesn't work as a climactic end to the quest for the fifth Star Piece and make you fight like hell to get it back from him.
The Axem Rangers, a parody of Power Rangers / Super Sentai that you fight three-on-five atop their airship, the Blade. And then when you beat them, they activate the airship's primary weapon, the Breaker Beam. It is not unexpected to see a party member drop to the ground after it hits.
The battle with Exor atop Bowser's Keep, Mario and his allies leaping into the fray atop a turret to face the giant sword face-to-face. The entire game has been building to this fight, and it's another Puzzle Boss with you having to incapacitate the eyes on the crossguard to damage the real target, the face on the pommel. Which happens to be the only boss in the game vulnerable to a timed hit from Geno Whirl, allowing you to deal it a One-Hit KO.
The final battle with Smithy himself. He's a shapeshifter who will rotate his head through various attack forms to debuff you, use One-Hit KO attacks, heal himself, deal devestating group attacks, and inflict status ailments on you. At 8,000 HP he has double the health of any other boss in the game, so prepare for a long, epic brawl.
For the first time in Mario history (unless you count Super Mario Kart), Bowser is playable. For that matter, Toadstool is playable too. Players can make the iconic trio a party and bring the pain on Smithy and his forces.
In addition, the two of them prove very capable as party members; Bowser makes for an incredible Mighty Glacier, while Toadstool is easily the best White Mage in the game. And even then, you can give Toadstool a Frying Pan of Doom in case you want her to pack a punch.
Bowser joins the party when he sees Mario stopped cold by a locked door. Bowser's response is to snap his fingers and slam his shell into it to smash it down.
As much as he's an Ineffectual Sympathetic Villain in this game, Bowser still terrifies the civilians of the Mushroom Kingdom. They panic at just the sight of him, and a growl sends them fleeing to hide shaking in the corners of the room.
When Mario gets to Bowser's Keep the second time, if Bowser is included in the battle, certain enemies will flee at the sight of him.
Toadstool refuses to sit on her keister letting Mario save the world this time, so she has her grandmother disguise herself as her so she can sneak out of the castle and join Mario's adventure.
The boss battle with Johnny Jones. At first he's nothing special, just another boss with a force of flunkies backing him up. Then after he Turns Red and you dispatch his flunkies, he's impressed with Mario's skill and challenges him to a Duel Boss battle. It's the first time since the Hammer Brothers fight at the start of the game that Mario has fought solo, and he single-handedly beats Johnny and wins the Star Piece.
There's a tiny one which doubles as a subtle Heartwarming Moment. When you first meet Mallow, his adoptive grandfather's coin's just been stolen, and, though he has been raised as a frog, he cannot jump. 6 stars' (and one recovered coin) worth of adventure later, Mallow's discovered that he's a prince, has found his true mother and father, and when he needs to jump onto the skybus taking the party to Bowser's Keep.... he does so. With aplomb.
Culex, a boss ripped straight from Final Fantasy that would invade Mario's world if he had the capabilities. Mario and his allies defeat him and prove themselves just as badass and powerful as any Final Fantasy hero, and are rewarded with the Final Fantasy IV Victory Fanfare and the series' iconic Prelude theme in the scene afterward.
Having your Attack button locked by Bowyer only invites your team to spam special moves. Cue the fireballs, lightning and laser beams making Bowyer really regret his decision.
After nearly 30 years, the game had been re-released on Vitual Console and even the SNES Classic, but it was hardly ever acknowledged. Now, not only is this classic SNES game coming, it's coming back remade, giving characters like Mallow and Geno their first new models in decades.
Remake
The climax of Bowyer's fight introduces the new Triple Move mechanic in the most badass way possible. Bowyer decides to subvert his weakness of only locking a single button at a time and fires arrows at the two unlocked buttons, also preventing their use. What seems like a Hopeless Boss Fight turns into Bowyer's downfall due to one simple fact: Triple Moves aren't mapped to either A, X, or Y, but Minus, and Bowyer can't lock that. (Well, he could, but due to Exact Words, this only blocked the use of Toad Assist rather than all moves bound to that button.) Mario, Mallow, and Geno then finish the battle with their first Triple Move, Star Riders.
Villainous points go to Bowyer's reaction. Instead of freaking out, he attempts to go for his own Triple Move. Sure, he can't because he's the only one there, but he certainly deserve points for trying.
The Triple Moves themselves are a sight to behold, with Mario teaming up with each of the party members in every unique combination possible to produce a new move that can turn the tide of battle.
"Star Riders" has Geno use the cyan Star Piece to call the power of the Star Road down to empower his, Mallow, and Mario's attack.
"Clown Car Barrage" has Bowser give Mario and Mallow a ride in the Koopa Clown Car, giving them a vantage point to rain down Fire, Thunder and Ice balls before Bowser finishes it off with a giant bomb from the Clown Car's main cannon.
"Healing Rainbow" has Peach and Mario lend Mallow some of their magic, and let the cloud prince use a supercharged version of HP Rain that heals the whole party.
"Spare-Us-All" has Peach channeling her protection magic into her parasol, with Mario and Geno helping to hold it aloft and creating a barrier to protect the party from the next incoming attack.
"Shooting Star Shot" has Bowser grab Mario and Geno, and toss them high in the air. Mario proceeds to grab Geno, and toss him even higher, allowing him to use his Star Cannons to their maximum effect. This is the same attack that knocked out Mario before Geno possessed the doll.
"Starry Shell Spike" has Bowser curl into his shell and leap into the air, with Mario following him. Peach proceeds to toss Bowser a Super Star just as Mario kicks him forward, allowing the Koopa King to barrel into the enemy without harm.
Axem Green and Blade get points for themselves simply by having their key attacks be magic, consequently No Selling the effectiveness of Bowser's Ally Buff against their offense. There may be flagrant workarounds against them both, but they, respectively a Squishy Wizard and a superpowered machine that uses only a Death or Glory Attack, still keep the Axem Rangers from being completely trivialized now by a Mighty Glacier of all people.
Mallow's own Ally Buff is not to be underestimated either. Although it is significantly more reliant on Magic Attack increases that are not as freely provided, it is nonetheless allowing shocking damage capability, to the point of seeing active use in Speedruns, as can be seen in this sub-3 hour No Super Suit run. Suffice to say that Bowser is not the only one redeemed from being a Low-Tier Letdown in the original by his Ally Buff, and some even consider Mallow's to be the best one, an opinion that may not be unanimous, but it is definitely built on a basis that everybody can agree with: that Mallow is an Adaptational Badass in the gameplay.
Smithy's boss intro is suitably menacing for the final boss, laughing as he displays his might by casting Sledge between him and the party. It serves as his final warning that you're in for the long haul with him, as he's just as likely to open the fight with it again.
While everyone else gets a beautifully done visual update with the newer graphics, Culex stays in his pixelated sprite… until the new rematch against him reveals Culex in all his now fully rendered, three-dimensional glory! His power is now in harmony with Mario’s world and is ready to invade unless you can stop him for good!
What makes it extra-awesome is that this rematch brings Culex's warning from the Super NES version full-circle. In the original Japanese, he was always intrigued by the power of the third-dimension but it was beyond his grasp, and in the localization he mused "in another time, another game, we may have been mortal enemies". Now, more than twenty-five years later, Culex steps into the modern era of gaming with a 3D model, a remastered battle theme, and more power than ever. It's almost as though he foresaw the remake coming all those years ago and has been preparing to face you, the player, in full 3D at last. And the player will likely be just as eager to have this destined rematch as he is!
The rematch against this beautifully redesigned Culex reveals that he is past, present, and future and has the power to consume all of time and space! And Mario and the gang still end up defeating him. That's right, Mario and the gang have the power to take on such a powerful godlike entity!
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