Java Edition:Stationary Projectile
Several projectiles are intended to travel in a straight trajectory indefinitely. These projectiles are ghast fireballs, blaze fireballs, wither skulls, and dragon fireballs. However, there have been and still are several methods to obtain these projectiles stationary. The first method that existed from 12w04a (1.2 snapshot) to 15w33c (1.9 snapshot) involved unloading the projectile to cause it to lose its motion. The current method works when a projectile spawns at the same location of its target. In this case, a glitch causes the projectile to spawn with no motion.
Obtaining
Unloading Chunks
If a projectile is unloaded either from leaving rendering distance into unloaded chunks or a player leaving the world/server stopping it will lose its current motion values and become stationary.[1][2] This works with ghast fireballs, blaze fireballs, wither skulls, and dragon fireballs. This method was possible from 12w04a (1.2 snapshot) to 15w33c (1.9 snapshot).
Target Position Being the Same as Projectile Spawn Point
This method works from 20w11a to 24w37a (present). When the target position is in the same location where a projectile appears, the projectile's power tag is set to [0,0,0], which will cause it to not move as it normally would. It can be done with ghast fireballs and wither skulls. Using ender dragon as a target it can be done with small fireballs with extremely small probability too. It may be possible to do with dragon fireball too.[test] This happens because when Abstract hurting projectile is shot, game checks if distance between it and its target is not 0 before setting power tag.
Ghast Setup
A consistent setup to get stationary ghast fireballs exists (pictured on right). The correct distance is 4 blocks out from the center of a ghast and the player's feet should be 1.75 blocks higher then the base of the ghast, this height can be accomplished with one block and an enchanting table. The player needs to be in the center of the block, one way to accomplish this is to be ejected from a minecart on an activator rail. Once the player is in this location, the player should hold sneak and then the ghast will shoot stationary fireballs directly inside the player that will not explode. The ghast can be held in a minecart at the center of the block or using guard railing blocks. A world download for 1.17.1 with this setup created by jjl211 can be downloaded at this link.
Wither Setup
To do: Test method version range, describe it, and screenshot it
From 21w03a (1.17 snapshot) to ≥1.17.1[test], stationary wither skulls can be obtained.
From >21w05b[test] until 1.17, killing the wither will kill all its loaded[test] wither skulls. Killing the wither while the skulls are unloaded will not kill the skulls.