DKSMS

DKSMS, also known as insta-siege, is a glitch in Doom (2016) that allows firing the Gauss cannon's siege mode without the charge-up animation.

Requirements and Execution
To execute this glitch, one needs to possess the following: While not a strict requirement, equipping the Rich Get Richer rune is recommended, since a single DKSMS shot consumes double the ammo of a normal siege mode shot.
 * The Gauss cannon with siege mode equipped;
 * Any other weapon to switch to;
 * 60 or more cells.

To execute this glitch, one needs to follow these steps:
 * 1) Equip any weapon besides the Gauss cannon;
 * 2) Switch to the Gauss cannon;
 * 3) Hold down the right mouse button. This may be done either before or after switching to the Gauss cannon;
 * 4) Hold down the left mouse button before the weapon is fully raised, while still holding down the right mouse button.
 * 5) Continue holding down both mouse buttons until the shot is fired.

Tactical analysis
One needs to be careful using the glitch without Rich Get Richer, as it consumes 60 cells per shot, meaning that players can burn through their ammo supply rather quickly (only two shots will be available without any ammo upgrades).

While this glitch removes the charge-up animation, it does not remove the cool-down after firing, meaning that spamming this glitch is impossible. The cool-down time can be spent by firing a single shot from the rocket launcher and two shots from the mastered super shotgun, leading to the highest possible DPS outside the use of the BFG-9000 or the chainsaw. The exceptional damage output proves the DKSMS-Rocket launcher-SSG combo to be particularly useful for bosses.

Trivia
The full name of this glitch is Dreamer-King's Siege Mode Shot, named after Dreamer-King, the speedrunner who initially discovered this glitch.