Every class can be used once, so in every game, there's just like one archer, one Assassin, one Runner, etc. But of both teams of course. There can't be like two guardians or something like that. There are several classes, and I'll show you what they all have, and what their ability's are. Here they are :D
The standard class, just iron armor, and an iron sword with Sharpness I on it.
Leather armor and a bow with Infinity I on it.
Guardian (Slowness I)
The guardian is like the tank class. He has diamond armor, and a diamond sword. He also has Slowness I, which doesn't have a time limit. He is like slowed forever.
Runner (Speed II)
Leather armor and a wooden sword with Knockback I. He is very fast :D
He has no armor, all he's got is a golden sword with Sharpness X, which will break after you've used it 3 times. He is invisible and has , because of the poison. He is very sneaky, but will be dead after one hit. He also has throwing potions of blindness.
Has white leather armor, and a stick with Sharpness X and Knockback II. He also has throwing potions of Healing and Regeneration. Only the white team has the oppurtunity to choose this guy, the black team doesn't have this class.
The opposite class of the mage, he has black leather armor, and a blaze rod with Fire Aspect and Knockback II. He also has throwing potions, like the mage, but he only has potions of Instant Damage and Poison. Only the black team can choose this guy.
This guy has no armor, just a bow with Power V and a stone sword. He only has 5 arrows. He can buy new arrows in the shop.
This guy has mixed armor, and a diamond Battle Axe. His armor is enchanted with Thorns I, so when you hit him, it will automatically hit you back.
This is the golden class. He has golden armor, and a golden sword without Unbreaking, so he will have to buy a new one at his store.
This is one of the troll-classes. He has red leather armor, but his helmet is green. So he looks like a strawberry :P. He has poison potions and an appel with Sharpness X. That's all he has got.
Bunny (Jumpboost V)
The bunny has like no armor, except for Diamond Boots with Feather Falling 100 or something like that. He has slowness potions and the Holy Mackerel from Team Fortress II. That's just a fish with Sharpness X. The idea is that he can jump over the whole map, with like nobody hitting him.
This guy has white leather boots, pants and chestplate. He also has a pumpkin on his head with Protection III. He has an inventory filled with snowballs. He also has a stick with Knockback II. He can buy new snowballs in the shop if they ran out.