My only problem with Lost in the desert is that it does damage to the general, which I’ve mentioned in a different topic. But I believe that any spell card that can do damage to the general should really kept a close eye on, because doing damage straight from the hand is often not fun to play against. So making any card that can possibly do a large amount of damage by itself, can be a problem card. My only change would be wording it to deal damage to enemy minions.
I think in Vet’s case with Lost in the Desert its not just Thunderhorn, but also things that can move other minions around like Recombobulus and Repuslor Beast, steal things with Psychic Conduct (and Blindscorch/Equality Constraint if needed to lower the attack value), plus transformational spell with Blood of Air, that can all be possibly played on the same turn with Lost in the Desert. Which is likely to wipe most boards along with the damage to the general is a bit much.
I see what you’re trying to say, but the differences between Glacier Fissure and Lost in the desert are a bit far apart for the comparison to really work. Since Glacier Fissure can only work on 5 specific spaces/tiles (whereas Lost can in theory work anywhere on the board) and the damage it deals is mirrored so it can effect yourself and the opponent (whereas Lost only works on the opponent).
TL;DR version: My only problem is damage also hits the general and I would possibly change it to just minions. Lost works in combination with more than just Thunderhorn. Glacier Fissure isn’t a great comparison to Lost, but I understand what you are saying and trying to go with that.