It was something I had been meaning to do for a while now, but tonight, in the wake of #76, I finally went back and re-read Trial of Krang plus Dimension X. And I have to say, this one particular issue is probably one of the best-written in all of IDW TMNT. It's just so damn funny! This series' art is praised on a regular basis, yet hardly anyone mentions the writing, when it's just as top notch.
Hakk-R comes across almost like a Joss Whedon villain here. Which is fitting, considering that in the very next issue he goes after a character who, if not for his appearance, could very well have stepped directly out of Firefly. That bit when he starts to break under the weight of the ridiculous predicament he finds himself in (not to mention the weight of Cryin' Houn'!) right before Mikey leaps into the ring with a big splash-worthy "Cowabunga!" still has me in stitches just as much as the first time.
But speaking of the art and of things not many people may have noticed, there's one particular Easter egg I haven't seen discussed. At a couple of points through the fight, we get shots of the audience. If you look closely, several of the aliens there were lifted directly from this iconic page:
The creature with multiple eye-stalks in the lower left is particularly noticeable in this issue, as is the off-brand Triceraton and at least one other alien that I can't point out specifically but just know is in there too.
All in all, great stuff! Finding new things upon re-reading is the mark of a job well done.