Ladder

Ladders are objects first seen in the 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.

Donkey Kong
Ladders are found throughout Donkey Kong and serve as a connection between two platforms. In 25 m, Mario has to use them in order to get to the top and to avoid barrels and Fireballs, however, barrels can occasionally roll down the ladders and the Fireballs can climb up them as well. Some of the ladders are broken; Mario cannot climb these. He also cannot climb any ladders if he is carrying a hammer. Some of the ladders in the 50 m stage extend and retract. Mario can only climb those up completely if they are fully open.

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, also known as Arrow Blocks. If Mario jumps against one such vertical-facing 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 if Mario places another ladder within the first ladder's time limit, or any other placeable objects such as roads, Jump Stands, and blocks. After disappearing, the ladder can then be placed with the same block again.

Wrecking Crew
Ladders reappear in Wrecking Crew, where they serve the same purpose they did in Donkey Kong. The enemies, Eggplant Men, Gotchawrenches, and Foreman Spike, can climb ladders. A type of ladders, ladder walls, appears in this game, where they must be destroyed.

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

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.

New Super Mario Bros. Wii
In New Super Mario Bros. Wii, the only level to feature ladders is World 2-4, where they are made of ropes. Here, while strong gusts blow, the ladders are pushed up, making them unusable.

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.

Luigi's Mansion
Several ladders also appear in Luigi's Mansion. One of them appears in Professor E. Gadd's laboratory, though it serves no function, and a second leads between the Courtyard and the Bottom of the Well. A third is found on the bunk bed in The Twins' Room, and two are found on the Roof.

Super Paper Mario
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!"

Captain Toad: Treasure Tracker
Ladders also appears in Captain Toad: Treasure Tracker and its Nintendo Switch and Nintendo 3DS ports 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 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 75 m stages of Super Smash Bros. Brawl, and many more games. Also, they can also be added to custom stages.