Door
From the Super Mario Wiki
Doors are things found commonly in the Mushroom Kingdom; they can be entered and exited. Most people use them to get in and out of their houses. If the door is locked, a key must be found to unlock it. Sometimes doors lead to secret areas (as in Super Mario Bros. 2, where all doors created by a Potion lead to Subspace), or are needed to progress in a level. There are many kinds of doors in Mario games. Some doors are even alive, such as the Dorguys.
[edit] Gallery
A locked Door from the Yoshi series. |

