New Super Mario Bros./World 5-Tower

Bowser Jr. was kind enough to prepare an automatic lift to transport you up to his chambers. However, as with any diabolical piece of architecture by the mischievous Koopa leader, this feature turns out to be a death trap, as Spiked Balls roll across the rising platform attempting to impale you. With no midway checkpoint, you must survive this deadly onslaught of traps all the way to the top.

Level walkthrough
You will be dropped on to a moving platform as soon as you enter the tower, which will immediately start rising at a slow speed. You must stay on this platform for much of the level, which isn't hard to do because there's no gaps to fall off. However, you'll come to realize the danger of this stage soon enough, as a Spiked Ball rolls out of a hole in the wall. Following the trail of coins, you can clear this first Spiked Ball with a well-timed jump, which should also lead you into a Star Coin. The Spiked Ball quickly disappears into a hole on the opposite wall.

Another hazard will be picked up by the platform, a Dry Bones that is free to wander around with you on the lift. This is followed by another Spiked Ball. The Spiked Ball can take out the Dry Bones, so it is actually better to leave them alone. This Spiked Ball is still a concern, and it will bounce a few times off the walls, making it a constant threat. Once that Spiked Ball rolls offscreen, two more Dry Bones will join you, followed by two Spiked Balls that rolls across the screen once, likely knocking both Dry Bones off. One more Spiked Ball will roll in from the left side, only to disappear after one bounce.

Not long after, the second Star Coin should scroll by in the center of the screen. Watch out for the incoming Spiked Ball as well as the Dry Bones as you do. Soon, another Spiked Ball will roll on to the platform, forcing you to dodge both at once. Soon after the second Spiked Ball's gap, there are two blocks. The right one contains a 1-Up. Eventually, the platform will move up to a section of the wall made from brick blocks. A Giant Spiked Ball will break through the wall and on to the lift, while the two smaller balls roll off.

With the Giant Spiked Ball bouncing around, it is no longer safe to remain on the main platform. Instead, you have to rely on the smaller platforms built into the tower to stay above the Spiked Ball. From here on out, try to stay toward the right half of the tower. You will soon get to the third Star Coin above two blocks by the right wall. By now, the path splits. If you ended up in the left half of the screen, you must keep wall jumping over a section devoid of platforms as the Spiked Ball looms just below. The right side is easier, having plenty of platforms and no Giant Spiked Ball. The Giant Spiked Ball will soon roll offscreen, just before you get to the double doors.

Boss: Bowser Jr.
Bowser Jr. is back to his usual style of fighting, but this battle arena is the first that truly poses a danger. Bowser Jr. fights you on a platform covered with ice, with a bottomless pit below. The slippery surface is much more threatening than Bowser Jr. himself, since you might find yourself sliding uncontrollably into the abyss. Use jumps often to reduce your momentum and stop yourself from sliding.

Star Coins

 * 1) This coin appears not long after the level starts, at the right half of the screen. Following the trail of coins should let you time your jump over the first spike ball to the Star Coin perfectly.
 * 2) The second one appears halfway through the tower, around the center of the screen.
 * 3) Once the Giant Spiked Ball appears, stay at the right side of the screen. The Star Coin will eventually appear on two blocks connected to the right wall.