It was in the episode The Garden of Delights. And yeah I think it was a one off episode, with the whole "Just Say No." message.
Tygra has gone for my favorite, to my least favorite in this new show. The fact that he seems to be the only Thundercat that uses a gun, only ads to that. When you are out trying to rebuild your lost world, an intelligent architect is far more useful then a glorified frat boy. I mean when it six of you in the wilderness, a guy with the knowledge of how to design and build structures, is more useful then the guy who can drink you under the table and fail constantly at hitting on the only thing with boobs in the group. The only thing that is making him useful in the new series is his fighting abilities, but the old Tygra had those too.