A Mario game just wouldn't be a Mario game without some bosses, and the New Super Mario Bros. series is one of the best because it brings the classic lineup of Koopalings (as well as some other notable baddies) back to plague Mario. Find out how to beat 'em all here.
The most common boss of the lot in New Super Mario Bros. U, Boom Booms typically appear as sub-bosses with their own fortresses halfway through worlds. Though Boom Booms gain abilities as you move through the game, none of them are terribly difficult - they all take three bops on the head to beat, and they move in predictable patterns. Keep away from each Boom Boom until they're solidly on the ground, then smack them on the head. Clinging to the walls is an easy way to stay safe as they rumble about on the ground.
The only exception is the final Boom Boom, which sprouts wings. In this case, stay in the middle of the room and wait for Boom Boom to sweep down at Mario. Once it does, jump and smack it on the head. Get out of the way as it recovers, wait for it to fly back to the ceiling, and repeat.
The first of the Koopalings, Lemmy's a cake walk as a boss. He spends the whole battle balanced on an oversized ball which is just small enough so you can stomp his head with a well-placed jump. Avoid his slow-moving, bouncing bombs (or bounce off them if you want a bit of a lift) and stomp his head. Avoid his shell as he moves along the floor, then repeat. Do this three times and he's finished.
With the proper handling, Morton can be even easier than Lemmy. His battle takes place on a platform with a pit on either side. Stay on the far side from Morton and avoid the chunks of Pokey he'll send your way with his hammer. Most will travel horizontally, but occasionally one will bounce high, so maximizing the distance will make dodging easier. Once he's out of Pokey to knock at you, run over and stomp his head. He'll retreat into his shell. Follow the shell as it moves back and forth and wait for him to emerge. When he does you have a few seconds to stomp again before he summons another Pokey. Do this twice and you can beat him easily.
Unlike most of the Koopalings, Wendy allows the environment to do most of the fighting for her. She spends the majority of the battle sliding back and forth on an icy floor, stopping only occasionally to launch rings that can knock icicles off of the ceiling. Stay still between two of the icicles and wait for Wendy to skate towards you, only moving if necessary to avoid her projectiles. Stomp her whenever she gets in range, then jump over her shell as it slides around the stage.
Perhaps the most mobile of the Koopalings, Larry like to change elevation a lot by both jumping and riding atop water spouts. Stay high on the stage, riding the water spouts whenever you can, and wait for Larry to stop and aim at you with his wand. That's your chance to catch him on the head. Be especially careful when Larry goes into his shell, as he'll rise up the water spouts in a hurry and can catch you off guard.
Bowser Jr. Part One
Your first battle against Bowser Jr. is an underwater scrap, with Jr. riding gleefully in his clown car. Jr. can't hurt Mario through touch, so he'll instead release heat-seeking torpedos to track Mario down. Swim behind the clown car and let these torpedos smack Jr. instead to do damage. Try to get Jr. with the first torpedo each time, as dodging more than one simultaneously can be tricky.
Another highly-mobile pest and probably the fastest amongst his kin, Iggy uses four pipes in his room to keep out of Mario's reach. He'll start by running through one and appearing on the ceiling, then launching fireballs from his wand downward. Avoid them, then watch out for the lava monster one of them spawns. Wait in the middle of the room for Iggy to run back down to the ground and catch him on the head. He gets faster and more unpredictable with each hit, though the process is always the same. Try to get him whenever he stops - he's fast enough to screw up your jumps if you try to nail him on the run.
Boss Sumo Bro.
The head of the Sumo Bros. replaces Boom Boom during one sub-boss fight, and he's surprisingly tough if you're not light on your feet. The Boss Sumo Bro. alternates between three platforms, slamming down sparks that will zap Mario. The moment he lands on one of the side platforms, hit it from beneath to knock him off his feet, then keep hitting the bottom of the platform until he falls on the ground. Perform a downwards stomp (jump then press down) to do damage. You can get him on the platforms, as well, though he takes up a lot of space and can make jumping difficult in such a confined area.
Another Koopaling who looks a lot tougher than he is, Roy battles with platforms and a big, nasty cannon. Hop onto the moving platforms when the battle begins and fall down on his head to drive him into his shell. Follow the shell as it moves back and forth (be careful when jumping - it's a big shell) and wait patiently for him to emerge, usually near the centre of the platform. The second he does, catch him in the head. If you're fast enough you'll completely interrupt his attack order, like Morton, and turn the fight into a joke.
Bowser's right-hand sorcerer is more frustrating than difficult. Kamek will stay far from the ground, using his wand to target Mario and turn the ground into unstable donut blocks. Wait for platforms to appear, then get to the top middle of the lot and wait for Kamek to teleport. The second he appears, launch yourself in his direction and stomp him. Don't bother trying to get Kamek at any other time, as he'll probably vanish before you can reach him.
The oldest Koopaling of the lot also gets one of the toughest boss fights in the whole game, though it's not so bad if you watch Ludwig's projectiles. Ludwig begins by leaping into the air and splitting into three, only one of which you can damage. Each one will launch fireballs at you; the real one will fire three, while the fakes launch two. Wait for them to descend and start hopping around, and stomp the real Ludwig. After zipping about in his shell and recovering he'll fly into the air and repeat this process. Get him two more times for the win. Don't try to stomp Ludwig just as he's coming out of his shell, as he'll almost certainly knock Mario back without taking damage himself.
Bowser Jr. Part Two
Your second brawl with Jr. is on a high-flying series of fragile platforms, and Jr., still in his clown car, now has boxing gloves. One hit from the gloves will damage the blocks you're standing on; another will take them out completely (though they will reappear). There are two ways to hit Jr.
First, wait for him to zip down to your level and start punching. Jump on his head as he zooms by.
Second, typically for the latter half of the fight, wait for Jr. to slam his arms down at you at an angle. So long as the arm is at enough of a diagonal, you can climb up and get him on the head. Try to stay as far away from Jr. as possible when he's aiming at you to make running up to him easier.
The punches aside, the only things you need to watch out for in this battle are the Bob-Ombs he releases. They're only minor nuisances.
Yep, after all is said and done you need to face down the head of the Koopa clan himself - though Bowser is a big enough threat that he warrants his own hub. Be warned: Bowser may still only take three hits like the rest of the bosses, but earning those hits is challenging. Prepare yourself here!