Nat

Three amigos. The built-upon house. 1929.

Attraction and Repulsion. Modern views of electricity. 1892.

Hanging flower basket in the shape of a cicada (Semikago) / Suzuki Gengensai

Top: cannons that fire the Kongs to bonus rooms are a recurring object in various levels of Donkey Kong Country 2. This footage shows a typical example of how one is activated; a cannonball must be found in the level and brought to the cannon, which will turn it green, showing that it will shoot them to the bonus level when entered.

Bottom: however, surprisingly, using a cannonball is not the only way to activate the cannon. Barrels shot by enemies will also turn it green, though that requires finding an enemy that shoots barrels and then escorting the barrel to the cannon so that it does not despawn.

Notably, this was only documented in 2025, 30 years after the game's release, despite requiring no glitches and being relatively easy to perform - possibly simply because no one involved with analyzing and speedrunning the game expected this interaction to work.