Neighbors.

[Althengo]

When I play skywars, I immediately get stabbed or thrown off a cliff because the dude next to me is Barry Allen and can bridge at the speed of sound. How do I counter this?

 

[DrogonMC]

With a bow, eggs or snowballs

 

[Rainzy]

With a bow, eggs or snowballs

Even a fishing rod, but I'd suggest place blocks infront of him and try knock the player into the void.

 

[MarcoXD192]

try to push him off before he gets to you, or use knockback items