In Dead Space in the stage 'Dead on arrival' you will encounter Twitchers.Twitchers are what remains of the U.S.M Valor's crew. They have a resembIence to Slashers, though much bulkier and they have a grey skin tan. Their voices (if you could call them voices) are much deeper than the usual Slashers, and they seem to run in zig zags. This is due to the built in rigs the crew of the Valor had. The infection process melted them into their skin, making them easily seven times faster than a Slasher. I recommend looking at the list below:

flamethrowers will not slow them down itt will only increase the damage they do.

pulse rifles will slow them down as long as you hold the trigger.

plasma cutters will make them studder for a quick second but theyll be right back to it.

the contact beam will kill them instantaniously.

the force gun will make them studder for 2 seconds.