Treyarch has stated that Call of Duty: Black Ops 4’s MP movement system is back to the basics: it’s 100% boots on the ground, but sliding is available in game.
There are no thrusters; there is no wall running. Back to boots on the ground, just like Call of Duty: WWII. The sliding mechanic is similar to Call of Duty: Black Ops 3. There is also the mantling system, to easily go over barriers. The movement system fluidity can somewhat be compared to that of Call of Duty: Ghosts, where sliding was available — while still being boots on the ground.
The swimming mechanism is also back from Call of Duty: Black Ops 3. Players can move around in water, where available in maps, and shoot their weapons as well, just like Black Ops 3. One of the things players will have to adjust to is not being able to quickly leave the water – in Black Ops 3, you can boost jump out of the water, but since this game is all boots on the ground, in some instances, you have to find the ladder nearby to get out of the water. It makes using the water a tactical decision that you have to consider.