IMPETUS is the first level of BIT.TRIP Runner. It contains eleven stages, one boss level, and two songs, those being Impetus and Strength. Additionally, it features eleven Retro Stages.
The level features a colourful, spacial aesthetic, featuring bright crystals, alien formations and strange otherworldly lifeforms, all beneath a beautiful starry night sky. It's here where CommanderVideo learns to jump, slide, kick, and use springs, and where he meets Junior Melchkin.
It is preceeded by SUPER-EGO and followed by TENACITY.
STAGES[]
1-1[]
This Stage teaches you to time the Jump correctly to avoid Obstacles and get Gold as well as Cores and is the easiest one of the game by far.
1-2[]
This Stage introduces you to the Holes, that you can just jump over like the Obstacles or Slide over once per time you hold Slide. It also features features stairway-like Obstacles where Jump must be timed, and branching path segments where you decide if you stay up and jump over platforms or fall down and get different and usually harder Obstacles.
1-3[]
This Stage teaches you to Slide and to time it, and Hanging Obstacles.
1-4[]
Some people who have just started this game yet may think the UFOs are POWER-UPs. You can see a yellow asteroid from Beat showing up in the background as an easter egg.
1-5[]
This Stage teaches you to kick Instable Obstacles, crystals in IMPETUS and stop-sign-like-octogons with a sad face from TENACITY on. They don't show up in the bonus levels, though.
1-6[]
As the name obviously implies, Junior Melchkin appears in this Stage. This stage tries to confuse you by regularly changing heights in the stage and thus altering the camera, and repeating things long enough where on your first playthrough you could ask yourself when it stops. It also pauses sometimes and resume right after in effort to catch you off guard.
1-7[]
This stage introduces you to Springs, which can just simply be used by holding up, but in order to catch all the Gold and COREs, you sometimes have to press up a few frames later. It ends off with a dozen Obstacles with Gold right behind them, getting too cocky on this part can make you restart the whole Stage. Jabol Smabbler could be the skeleton-like giant seen multiple times in the background, but it is unlikely since in Smabbler's Groan, the next Stage, that creature can be seen twicce on the same screen.
1-8[]
You sometimes will have to use two Springs consecutively in this Stage. Holes will more often than not lined up weirdly in an attempt to get you confused and jump around straight into one, but all you actually have to do is jump over the first, ignore the second and jump over the third.
1-9[]
This Stage is all about repetition. At the start, it repeats a sequence over again: jump-kick-jump, jump. After that, it uses another sequence twice, and follows up with a really, really long repetitive branching path segment. Then, you have to jump, slide and jump over and over again ending with a spring, all twice in a row. Then it uses the first pattern again before making you spring twice.
1-10[]
From this Stage onwards, you will have to dodge Bouncing Blocks. They appear in two forms: Orange Blocks that must be jumped over, and Purple Blocks that must be ducked. Otherwise, there is also repetition in this Stage, but not as much as in the previous one. There is also a tricky tunnel section that quickly changes layers up- and downwards, it's quite easy to get confused and jump against the ceiling or forget to jump. Then there are two very long stairway-like Obstacles and a few patterns.
1-11[]
This stage is a major wake up call for the player. It is disproportionately more difficult than the grand majority of the entire game. It has a whopping 93 Golds to collect and a vicious gauntlet of nonstop obstacles for the player to overcome, including numerous springs that require precise timing to collect every Gold. It progressively but frustratingly slowly goes through everything that has been learned so far.