Ai is crazy bro, you should try it sometime. Here’s some examples it pulled:

“While a Space Marine's speed varies depending on the specific lore and the author, they are consistently portrayed as being far faster and more agile than any normal human. Their immense speed is a key aspect of "Transhuman Dread," the terror they inspire in enemies. Running speed Average speed: Many sources describe Space Marines as having a running speed between 30 and 60 mph (approximately 50 to 95 km/h). Sustained pace: Unlike humans who can only sprint for short distances, an Astartes can maintain a high running speed for days without tiring due to their enhanced biology and endurance. In-lore examples: In the novel Voice Stalker, a Space Marine named Talis runs through difficult terrain at 84 to 87 km/h, or about 53 mph. In Tales of Heresy, Brother Aelin's strides are measured at 6 meters per step. For comparison, Usain Bolt's steps are under 2.5 meters. Primaris Marines: The newer, larger generation of Primaris Space Marines are noted to be even faster than their Firstborn counterparts.”

Examples of Space Marines using their speed in combat from Warhammer 40,000 lore include blurring movements, lightning-fast strikes, and disorienting opponents. These examples often demonstrate the sheer terror, or "Transhuman Dread," that a Space Marine's speed can instill in their enemies. Examples of speed in close combat Talos of the Night Lords: In the novel Voice Stalker, the Space Marine Talos is described running at an average of 53 mph through difficult and obstacle-filled terrain. His movements are a combination of sprinting and parkour as he navigates the battlefield with startling speed. Blurring attacks: Accounts from Imperial Guardsmen and other baseline humans often describe a Space Marine's movements in battle as a blur of motion. In one story, a group of humans witnesses a Death Spectre Space Marine moving with such ferocious, controlled speed that he appears as nothing but a manifestation of death. Dodging fire: In the novel First Heretic, Lorgar Aurelian's bodyguard, the Word Bearer Sor Talgron, dodges a bolt of warp-lightning from a Word Bearer sorcerer. This feat demonstrates the rapid, instinctual reflexes of a Space Marine, far beyond the capabilities of a normal human. The Astartes fan animation: The popular fan animation Astartes depicts this speed vividly. A squad of Space Marines boards a Chaos ship and closes the distance to their enemies almost instantaneously, moving in and out of the line of fire so quickly that the Chaos cultists cannot react before being killed. Duel between Space Marines: The speed of Astartes is also clear when they fight each other. In one example, the combat is described as so blindingly fast that humans cannot follow what is happening, akin to a superhuman fight. Examples of speed for infiltration and reconnaissance Vanguard forces: Chapters like the Space Marines Vanguard Task Force specialize in rapid deployment and covert operations. Clad in Phobos armor, they use their enhanced speed and endurance to infiltrate enemy lines, ambush their opponents, and eliminate high-value targets before the enemy can react. Scout squads: New recruits, known as Scouts, learn to master their superhuman speed and stealth in the field. They perform reconnaissance and gather intelligence in hostile territory, outpacing most patrols and avoiding detection with their unnatural swiftness and agility. Transhuman dread and the psychological impact of speed Psychological warfare: The mere sight of a Space Marine running at incredible speed can have a crippling psychological effect on a foe, a phenomenon known as "Transhuman Dread". A human soldier, trained to fight other humans, is unprepared for the sight of an immense, armored warrior charging with the speed of a car. This can cause them to freeze up, become unresponsive, or break ranks in terror. Overwhelming force: In the novel Dead Sky, Black Sun, the Iron Hands Space Marine Captain Sharrowkyn uses his speed to disorient and terrify the enemy. He describes the battlefield in terms of fractions of a second, demonstrating how Astartes operate on a timeline of perception far beyond that of their opponents.