If you are just starting out and haven't unlocked the create a class. You can use the default class called
Wrath Hammerr. At the start of the match go through one of the red teleporters, and you will be teleported to a random area of the map. Here you will be given some type of challenge whether that be survive for a certain amount of time, get a certain amount of kills or escort a golden ball around. Complete the objective to progress to the next round.
Keep going through the teleporters until about round 5 or 6.
Once you're back in the main area, get a large group of zombies by looking at the map for all the red dots. Then simply just pressing
and
at the same time to activate the Ring of Fire Artifact. When eliminating the zombies from inside the Ring of Fire you will see the text "Zombie Ring of Fire kill".