This is a true story. What the comic does not reveal is that this unfortunate incident resulted in the hapless rogue dying from his "self-inflicted" impalement.

In the world of DnD, rolling a 1 on a 20-sided die is an automatic failure of whatever attempted action the character was in the act of performing. After a 1 is rolled, the die is rolled again. If the second roll is also a 1, the effort is deemed to be a 'critical failure'. This not only means the character failed in his attempt, but also that something bad happened as a result of his actions. In the above case, failing the Climb Check resulted in him falling on his sword and expiring due to low health points.