Did anyone manage to achieve the gold rank in the Odran Valley quest (no. 7) of the Last Midnight campaign? Is it possible at all?

I managed to achieve gold rank in all quests of all campaigns, but this one is the only one where I can just get the silver rank. I've tried various strategies already:

1. Killing all Unicorns with the Sorceress: Takes too many turns because the movement range of the Sorceress is just 1 until she levels up. Note: I moved the Goblin to the upper right corner in order to bypass it with the Sorceress and thus saved some turns, but it didn't help.
2. Imprisoning eight Unicorns and killing the ninth: Also just results in the silver rank. Probably too few fights won for a gold rank, I don't know.
3. Killing all Unicorns with the Goblin: I just can't seem to do that. One of them always kills the Goblin, especially because they just fight on the white squares.
4. Taking both power squares: Results in the silver rank as well. Reasons might be the same as under 2.

Any ideas? Does anyone know what exactly it takes to achieve a gold rank in general? My impression is that winning lots of (or better: all) fights without losing a unit and/or winning with just a few turns is the key to get the gold rank. However, this seems to be impossible to do in that particular quest, due to the reduced movement range of the Sorceress. So the only strategy I can think of would be to kill all Unicorns with the Goblin. But as written already, I constantly fail in doing this.

The requirements for a gold are listed on the mission briefing screen, on the side I think? I can't really recall. The top number is wins, the middle number is turns (?) and the bottom is total losses, which is probably 0 in this level. That should help... not necessarily saying it'll help you win, though, that's a rough level to overcome just normally, much less for the gold.

You're attacking eight (8) unicorns on light squares with one (1) goblin? Remind me to be really careful around you when network play is available

Blackdrazon: Thanks for clearing up where to find the criteria for gold. I've been wondering about that for a while now.

Think outside the box here. There is a way to win this in 6 turns, with no Imprisons used. I don't want to be a spoiler here. So if you really are tired of trying to figure it out, message me!

Ahh, I must be blind! I totally missed that the Sorceress also has the Level Up spell. Since it was at the end of the list, I didn't ever read it, but instead regarded it to be the Cancel button. Ok, that was easy to do now. Thanks to you guys for helping me out!

Lol, and of course I also never read what's below that picture in the mission briefing. To know that in advance would have made things a lot easier. Now I just learned it when I'm through already.

That would account for the difficulty, then!
The first time I did it, I Leveled Up the Goblin, used all the Imprisons and the Shift Time, and beat the final Unicorn with the Goblin! Then, I realized how easy it would be the "other" way!

The criteria for getting medals is also In-Game on the bottom right of the screen.
Surprised no one noticed that.

Good job on figuring that one out. I like that it makes you think a little outside the box.