Characters (Risk of Rain)

There are currently 10 playable classes available.
 * Commando
 * Miner
 * Bandit
 * HAN-D
 * Engineer
 * Huntress
 * Acrid
 * Sniper
 * Enforcer
 * Mercenary

Each class features 4 different skills.

Commando
Available from start

Bandit
Unlocked by: Completing Level 3

HAN-D
Obtain by opening a crate on the final level. (Not sure if random)

Engineer
Unlocked by: Buy or repair drones of total 40 times

Huntress
Unlocked by: Collect 15 Monster Logs

Acrid
Unlocked by: Defeating the Acrid in the Sunken Tombs

Sniper
Unlocked by: Complete the game once

Enforcer
Unlocked by: Kill 3 boss types (Magma Worm, Vagrant, Giant Stone Golem) 

Mercenary
Unlocked by: Complete the game 5 times