Prove Yourself is the first and only mission in the Mad Moxxi's Underdome Riot add-on. Upon entering the Underdome for the first time, head down the stairs and the The Underdome Bounty Board will come into view. Interact with the board to pick up this mission.
- "In order to access the longer tournaments, you'll need to prove yourself by completing 5 rounds in each coliseum."
In this mission there are 3 arenas that must be completed, by way of surviving 5 rounds in each. All five rounds of an arena must be completed in one session. You can save in the Underdome after finishing each arena, but if you exit an arena, you will start again at round one the next time you enter it. Each of the 5 rounds consists of 5 waves: The Starter wave, the Gun wave, the Horde wave, the Badass wave, and last, the Boss wave.
- The starter wave consists of normal enemies ranging from bruisers to psychos. This round is the easiest of any, no real strategy here.
- The gun wave consists of enemies that have guns, usually bruisers and bandits, with the occasional Lance troops. Typical borderlands, really. Again, no real strategy here.
- The horde wave consists of psychos and midgets. For this round, use a close-range weapon and run circles around them. Never become surrounded, in the later rounds one hit or grenade from a psycho is lethal. However in Hell-Burbia and Angelic Ruins there are places where enemies can not get to, while the player can. Those places are optimal during a Horde Wave since the psychos will swarm around the Vault Hunter and can't attack.
- The badass wave has tougher enemies ranging from bruisers to Crimson Lance and guardians (all except sera guardians) and it seems that the guardians are seen more often in The Angelic Ruins. There is usually a mix of normal badass enemies. For this round it is recommended that you maintain a comfortable distance and utilize long-range guns. Note that Lance Soldiers and Guardians will fight each other, unless attacked by the player(s). Keep your distance, watch, and deal with the pitifully few survivors.
- The boss wave will introduce one of the bosses from the main game, such as Nine-Toes, King Wee Wee, and Baron Flynt. Most of these bosses will have support (for example, Nine-Toes has his two skag pets Pinky and Digit, Master McCloud will have a pair of Lance Royal Guard, others will have normal bandits, bruisers, etc.). Utilize the same tactics as in the vanilla game to defeat the bosses and move on to the next round.
- Opposing factions such as Human, Guardians and Skags will begin to fight each other until the player intervenes. If the player so chooses, he/she can opt to stay back and allow their opponents to kill each other off before entering the fray. In this case Bandits and Lance are considered same faction and cooperate each other.
By round 2, Rules start to kick in and by round 5 there are two active rules per wave. There are many rules that range from lower gravity or tougher enemy shields to specific weapon types being more powerful than others. In the 5 round matches, the most rules in effect at one time is 2, but in the 20 round matches you eventually stack up to 4 rules. Since the rules are set randomly they sometimes have no effect on the current wave of enemies. For example: the Loaded rule that gives enemies larger clips will sometimes activate during a horde wave.
- See also: Underdome gameplay mechanics
- "You've proven yourself... at least a little bit. Now that you've gotten through round 5, step behind the curtain and see if you can get to round 20!"
- Though there are no following missions, after Prove Yourself is completed, the larger tournaments become available. The three larger tournaments are played in the same arenas as before; however, they will run up to 20 rounds, which is 100 waves. There is no in-game reward for completing the larger tournaments.
- This was the only mission to grant a Skill Point as a reward before the release of Claptrap's New Robot Revolution. It can be completed twice: in Playthrough 1 and in Playthrough 2 to obtain a total of 2 Skill Points. This, in combination with the level cap of 61 in The Secret Armory of General Knoxx, plus the 8 from Patch 1.4.1, brought the maximum possible amount of skill points (without modding) to 67 (since the first four levels have no skill points) and then there are two more for a total of 69 with Claptrap's New Robot Revolution.