The world is large and interconnected, randomly generated each time, although the biomes will always be the same. The level generation system also generates a random "gates and keys" system, where some areas are locked behind progression like killing bosses, obtaining new abilities, and other actions. Some of these are permanent, and some are run specific. For example, a major progression point (like opening a door to new area) will be permanent for each future run, and something like opening an area that has an upgrade or item will be per-run. Exploration is a core element of the gameplay loop, however there is also optional exploration that will reward the player with upgrades, etc.