Vertical Speed Conservation

**Vertical Speed Conservation** (VSC) is a technique that takes advantage that certain actions of Mario do not reset his vertical speed to 0 when landing. Furthermore, there are a few ground actions of Mario that does not reset his vertical speed. If Mario can then leave the ground without setting a new vertical speed, he can effectively reactive his speed gained prior to landing.

## The timeline of a VSC

There are three parts to a VSC: When the speed is preserved upon landing, when the speed is maintained on the ground, and when the speed is reactivated in the air. If a positive vertical speed is stored properly, Mario can gain precious height while being in a freefall state, allowing Mario to grab onto ledges where a dive recover cannot, or using the misalignment of a corner to ground pound onto the floor.

### Preserving vertical speed upon landing

The Vertical speed is in effect only when Mario is in the air. As such, the vertical speed does not have any effects during his ground movement. Usually, the speed will be reset to 0 when Mario lands, but there are cases when it is not. These actions include:

* Landing from a dive recover (most commonly seen)
* Landing on a ground pound
* Landing on a slide kick bounce
* Landing on a lava boost
* Landing from a twirl (from a Shy Guy, a Spindrift, etc.)
* Landing from a dive with an object held
* Entering the first person mode on the frame Mario lands
* Landing immediately when the in-game text starts
* Landing when a cutscene begins (where Mario is unable to move, such as the Chain Chomp cutscene)
* Landing after collecting the star, exiting the course

### Maintaining vertical speed on the ground

Many actions will reset Mario's vertical speed to zero when moving on the ground, such as walking, running, and crawling. Jumping will override the preserved value with a new one depending on what type of jump Mario is performing. However, the following actions do not affect Mario's vertical speed:

* Punching (by pressing B) and punch-kick combo, as long as there is no contact with an enemy or a wall
* Crouching (by pressing Z), staying in place
* Breakdancing (punch while crawling), as long as there is no contact with an enemy or a wall
* Grabbing an object
* Dropping an object
* Throwing an object
* Not moving at all on the ground

### Reactivating vertical speed

There are many ways to leave the ground to reactivate the vertical speed. Mario obviously should not jump since a new vertical speed value will be used in its place. Actions that allow speed reactivation includes:

* Having the floor below Mario disappear (or become intangible)
* Having the floor move out from under Mario (and he does not move with it)
* Pushing Mario out of a platform with a wall or an object collision
* Standing on an edge of certain moving platforms to fall off due to float-to-short imprecision
* Having Mario move off the floor under him (by punching towards an edge of a platform, or a floor gap), and he can snap onto floors 78 units higher and down to floors 100 units lower to avoid getting off the ground

## Applications

In an A Button Challenge, as Mario cannot press A to jump, storing vertical speed is most commonly done by performing dive recover. As a dive recover has the initial vertical speed of 30 and decreases by 4 on each frame, resulting in a maximum of 26 vertical speed that can be stored if Mario lands on the first frame of a dive recover. This is called a VSC26 (having 26 vertical speed conserved).

It is the positive vertical that gets used more often since it is more desirable for Mario to be moving upwards, but it a lot more difficult. Additionally, Mario cannot encounter a ceiling, which would cancel his movement and reset his vertical speed to zero. Nevertheless, Mario can land with positive vertical speed stored by dive recovering on the following:

* On a steep slope, facing up hill with high horizontal speed
* On a different, higher platform whose height is at least 7.5 units apart
* On a rising platform

As a VSC26 is a dive recover with the first frame chopped off, he can gain only 98 units high, as opposed to 128 units high from a dive recover. However, being in a freefall state allows Mario to grab on ledges and ground pound to gain height. Still, there are strict limitations on how much speed Mario can store and how it can be reactivated.

### Ascending platforms

Maximum height reachable
 Corner (misalignement)
 SDC

The maximum height a dive recover can ascend onto is 156 units up when using a normal edge, and 206 units when using a misalignment. In comparison, a VSC26 can ascend onto a platform 247 units high with a ledge grab, and 274 units using a ground pound on a misalignment. Furthermore, if a star is involved, the combination of a dive recover and Star Dance Clip (SDC) can get on 298 units up, but the combination of ground pounding and SDC allows Mario to get on a floor 345 units up.

Examples of this action are as follows:

**A Button Challenge**

* Grabbing the edge of the second floor in Big Boo's Haunt using the ascending stairs, effectively saving 5 A presses for 120 star run as this action is required for 5 of the main mission stars.
* In Bowser in the Dark World, storing VSC26 using glitchy collision check of a crystal and punching towards a platform to ledge-grab, effectively saving an otherwise mandatory A press.
* In Hazy Maze Cave, storing 18 vertical speed using the Blue Coin Switch and Ground-pounding on it with the help of two swoopers, allowing access to collecting 100 coins in the course
* Grabbing a star in Tick Tock Clock using a 1-unit floor gap to pop up with VSC, speed being gained by the edge of a conveyor belt
* Grabbing onto the platform where to pole is located in Tick Tock Clock, first collecting a coin by a bob-omb on an ascending platform with VSC26 to spawn the 100-coin star as high as possible, and then use VSC26 ground pounding near an edge with Star Dance Clip, removing one of the A presses required to reach the pole.
* Dive Recovering onto a rising elevator in Whomp's Fortress, using a cork box released from the HOLP to reactivate VSC26 and land on the platform via Star Dance Clip.
* Landing on the platform leading to the floating ship in Rainbow Ride, using VSC26 and Lakitu Bounce on falling donut blocks

* An alternative method of ground pounding the post to free the chain chomp in Bob-omb's Battlefield, without cloning or using shiny shell
* An alternative method of ground pounding on King Whomp in Whomp's Fortress, using the misalignment of King Whomp and store VS2 and reactivate it with its edge, and ground pound to gain height for collecting the star
* An alternative method of getting to the platform with a spinning heart in the volcano of Lethal Lava Land, using the first-frame landing of lava boost onto a moving platform and activate VSC80 with a dive (slower than the current method of lava boosting on a lavafall)

**Non-A Button Challenge**

* Collecting the 5th secret of Mario Wings to the Sky using VSC 330 by jumping and landing the first frame with 914 horizontal speed, converting into 334 vertical speed with a double jump, and then being pushed off by a Bob-omb to reactivate vertical speed. Mario enters a freefall state holding a fake cork box to clone the top coin prematurely, effectively removing it and collecting the secret using narrow region of the hitbox where it is not overlapped by the center coin.

## Variations

**Vertical and Horizontal Speed Conservation** (VHSC), conserving both horizontal speed and vertical speed at once, occurs when Mario lands on the platform and immediately falls off on the second frame, putting Mario at a falling state but with horizontal speed intact. It can be achieved by having the floor under Mario disappear or moving out, but float-to-short imprecisions can also cause it.

## References

1. ↑ Vertical Speed Conservation: https://youtu.be/6md3RA8bH40