AFAIK, the result where your unit disappears can happen to ANY unit, so you can lose your uber-hero in the blink of an eye, no "saving throw". Then there are the results which can give your unit Wither or Diseased, which can make that uber-unit not so uber anymore, depending whether you have the resources to cure it. And almost as bad as the "disappearing" result is the new mechanic for the crazed promotion. Thank goodness your uber-unit doesn't turn barbarian anymore, but it's basically not your unit anymore either. Other negative results are more survivable by higher level units though, of course. Somebody remind me, is it just the scout and ranger units who get better results from exploring lairs or is it any recon unit? And can a scout explore a lair while on a ship (resulting in better results for shipwrecks and Aefon Isle)? Oh yeah, and waiting until you have higher level units to explore can also mean you lose the chance altogether. The AI may not explore lairs much, but other human players certainly will.