Ladder

Ladders are objects first seen in original Donkey Kong game. They have reappeared throughout many later games as inanimate objects that the player is able to climb to progress in the level, area or stage. As shown in Super Paper Mario, Bowser is unable to climb up the Ladder, most likely due to his size. If he tried, he would struggle and mutter "Can't climb this!". However, Bowser is fully capable of climbing ladders in Super Smash Bros. Brawl.

Donkey Kong
They are found throughout the stage and serve as a connection between two ramps. Mario has to use them in order to get to the top and to avoid Barrels and Fires. Some of the Ladders are broken; Mario cannot climb these. He also cannot climb any Ladders if he is carrying a Hammer. The Ladders in the 50m stage extend and retract. Mario can only climb those up completely if they are fully open.

Donkey Kong (Game Boy)
Ladders reappear in Donkey Kong for the Game Boy in several varieties. The static and extending ladders from the original arcade game make a return in many levels of the game. Mario can only climb a ladder if he stands on solid ground, which is an important element in some levels, where he first has to place a Road or jump on an icicle to have a platform to stand on from which he can climb the ladder. Another important element in the game's puzzles are ladders than can be placed by Mario himself. If Mario jumps against a Ladder block in the game, the game freezes and the player has to place the ladder in any free point of the level. The ladder will then extend itself upwards and downwards as far as it can. The ladder is timed, and disappears after the time has passed. This timer indicated with a music that starts playing as soon as the ladder is placed and gets faster gradually. The timer can be reset to 0 if Mario places another ladder within the first ladder's time limit, or any other placeable objects such as Roads, Springs and blocks. After disappearing, the ladder can then be placed with the Ladder block again.

Super Mario Bros. 2
Ladders first appeared in the Super Mario series in Super Mario Bros. 2, where they function similar to beanstalks.

New Super Mario Bros. Wii
In New Super Mario Bros. Wii, the only level to feature ladders is World 2-4. Here, while strong gusts blow, the ladders are pushed up, turning them unclimbable.

New Super Mario Bros. U / New Super Luigi U
Ladders also appear in New Super Mario Bros. U in the level The Mighty Cannonship, and in New Super Luigi U in the level Broozers and Barrels. They behave the same as they did in New Super Mario Bros. Wii.

Super Mario Land
Ladders also appear in Super Mario Land's Bonus Game. One ladder, along with Mario, will move between the different platforms until the player presses. Mario will then move along the platform, but if he comes across a ladder, Mario will move up or down it onto another platform, collecting a different reward.

Captain Toad: Treasure Tracker
Ladders also appears in Captain Toad: Treasure Tracker which Captain Toad and Toadette can climb. During the levels that reappear from Super Mario 3D World, ladders were added due to Captain Toad and Toadette being unable to jump.

Other appearances
Ladders have made appearances as well in Super Paper Mario, Mario vs. Donkey Kong, Mario & Wario, Mario Party: Island Tour, Mario vs. Donkey Kong 2: March of the Minis, Mario vs. Donkey Kong: Mini-Land Mayhem!, the Rumble Falls and 75m stages of Super Smash Bros. Brawl, and many more games. Also, they can also be added to custom stages.

Two ladders also appears in the Luigi's Mansion. One of them appears in Professor E. Gadd's laboratory, though it serves no function, and the other leading between the Courtyard and the Bottom of the Well.