During my last Adventure’s League session, we played through the manticore encounter in the Princes of the Apocalypse module. Our half-orc barbarian set himself up as the comic relief and hero member of the group, as he took one dare after the next, and succeeded in each one with authentic die rolls, astounding us and our DM equally. He pretty much won the encounter for us, and we players all had a couple hours of fun and laughs. D&D as it was meant to be.
Not only is it in the DM hands to set the facts and figures of each session, the DM should also be aware of the tone of the game, as well as the persona of the PCs. Every now and then, or as often as you and your players like, set them up with some humor on purpose. Don’t always count on a player to bring it to the table.
Not every session has to be the PCs pitted against all the evils of their world. Don’t let your DM legacy be all doom and gloom. Give PCs a fun and funny break every once in awhile, and lead them into purely comedic adventures they may not encounter on their own. Role ‘em!