Well, a while back I managed to lose a game against Omnitron after doubting this would ever be possible; since then I've won against the Matriarch, and now I've lost against Baron Blade. In most cases, the surprising results are due to luck, but not always, and this was an interesting case.
Not a tough game at all, but the heroes were reckless in ignoring the Hayes brothers, who popped out of the Environment all in a row. Blade reliably discarded his best cards to the Advanced ability while playing mediocre ones, and this pattern was about to continue after I flipped on turn 6, when I revealed a Blade Battallion - but then I realized that I had forgotten to shuffle in his trash and discard the MDPs, so I took care of that, and the new first card he played on side 2 was Devious Disruption, the card he'd played on turn 1 for a mere 3 damage to everyone! This time, I opted to keep By Any Means and Pride, and an Explosives Wagon had come out (after two turns of Adhesive Foam Grenades) after he flipped, so 6 damage was dished out to all the bullet-riddled heroes, leaving Bunker at 1 and CR at 4.
Figuring the heroes needed to save their skins and having none of the right cards in hand, CR used a Ranger's Mark to put his only trashed Bounty, No Executions, onto the Explosives Wagon so it wouldn't kill all the heroes off. They then continued whaling on Blade, but the Environment produced Sustain the Portal for 2 damage to everyone, which became 3 due to the Explosives; this killed Bunker and left Blade to execute Expatriette. Stuck with a bad hand after the loss of all his best stuff, CR suddenly saw that if he hadn't put out No Executions on the Explosives Wagon (but had either put it on some other target or had used some other Bounty - he had two in his hand and must have had at least one on the previous round, though I don't remember when he drew them), he could have won...firing Danny-Boy once on his own turn and once on Expatriette's, he'd have taken out the Wagon while hitting Blade for 4 damage (+2 from Explosives and By Any Means, -2 from advanced text and Living Force Field), and Blade was down to 2 so the Explosives would have killed him (I think*). As it was, he left the Explosives out of the second Danny shot, and ended the round hoping that SG would Sustain the Portal again for 2 damage, which would kill Blade before him. And sure enough, Temporal Event came out and went looking for Time Portals...but after burning through the entire deck down to the last two cards, Lost in the Past was on top.
So Blade got his 9th turn, and his innate damage was going to kill CR anyway. But just to add insult to injury, his last card? Devious Disruption.
*(Quick question on the Explosives Wagon - is it "fire damage to each target in turn, then projectile damage to each target in", or "fire and projectile damage to one target, then fire and projectile to the next, and so on"? The latter seems closer to the card wording, and makes the "end the game with a bang" strategy more viable, as it means you can deal 6 damage to the villain without being able to survive 3 damage yourself. I'm basing my statement that Blade would have died on the assumption this is correct, even though it seems cheatier than having the damage be as global as possible.)