The Cube is the main attraction in Fortnite Battle Royale right now and it is still unclear what the Cube will actually change in Fortnite, but what has been discovered is the path the Cube will take. Here is the path that the Cube should be taking and where it will imprint the Runes on its journey:
We do know that the Cube will end at Loot Lake, but we do not know what will happen to the Lake once the Cube reaches this POI. With the v5.4 update, it looks like more audio files were added for the Cube. These have been discovered by data-miner Silox and they have posted a clip of all the sounds, which can be heard below:
New cube event audio pic.twitter.com/XWM9uHWnEe
— Prism (@pr1smdev) September 6, 2018
We can confirm that the Cube will travel to Loot Lake, due to files that have been found by @FNLeak which clearly mention this POI. There will be other things that will happen, but we do not know exactly will happen yet.
You can see the skins that were leaked with the v5.4 update in the article below: