Slayers have a simple job; all they do is kill people and that's it. They ensure a wipeout every five seconds and usually lead a push. Typically these weapons will be hard to kill and must be respected by the other team. They are typically weak to anchors. 

The Anchor player is always placed at the back of the team. This player is your team's last defense meaning if your whole team dies except for the anchor, they have to fight the whole other team while your team super jumps or swims over to you. This just means you are going to be the last line of defense for your team. Anchors usually can fight from a distance and are amazing at catching people off guard with unpredictable shots. These weapons will almost always be terrible up close, and their only option is staying in the backline positions. Anchors are typically hard to deal with unless you are also an anchor. Then it's fair game. 

Supports focus on the team rather than them self. They are the teammates that cover turf, and can't handle combat usually. A decent support special could be big bubbler or tacticooler due to them making your teammates more powerful. Supports struggle to fight anchors and frontlines slayers. 

The skirmisher is a member of a team which is tasked to go up and bother any player. This player does not want to get too close, just close enough to aggravate their opponent. The skirmisher shouldn't always be bold and visible.  Lots of chip damage is the key to this weapon role. But why? Well, this player sets up the perfect opportunity for the next weapon role to succeed, the slayer. Skirmishers are usually weak to anchors.

Flex isn't technically a weapon role, it's the name for a weapon that can do two roles depending on the situation. Let's say that you just killed the entire team, and you need to cover turf and play backlines. Flexes are usually the kings at doing this.