The sixth stage of the "Van Kanighem" tournament.

Did I guess right or not? :)

Well, almost. Some things were right, some weren't:)
The idea is as follows, in short:
Immediately head right and up to collect gold... I only took elves and about 30 sprites... On day 2, I took a gold mine. We don't touch the mercury near the druids... otherwise, we won't have time...
The second mage, with all the dwarves and 50 sprites, goes to the log mine, then she joins 2 stacks of archers and 1 stack of wolves... Mage #1 goes up and joins ogres... Barbarian #1 emerges from the castle and spends the night at the mine (which was guarded by ogres).
Day 4: Mage 1 gives the army to Barbarian #1 and gets into the boat... Barbarian fights gargoyles and ghosts, and on the last turn, he takes the boots... ALL CHESTS ARE TAKEN FOR MONEY...
Day 5: Barbarian #1 clears the path to the portal (HE DOESN'T TAKE ANYTHING EXTRA, neither mercury nor money!!!) and stops one step away from the portal. Mage #1 sails to the magic hut... Mage 2 gives her all (except one for herself for the turn) the wolves, 1 dwarf, and all the sprites... The remaining dwarves (about 70-80) and about 57 archers are destroyed... Mage 1 sails as far as possible.

Day 6: Mage #1 lands near the Yellow Castle (Warlock)...
Barbarian #1 dives into the portal... emerges in the desert, defeats Red Hero #1, and rushes, clearing out Normans, ogres, and thieves, to the Red Castle... defeats it and moves one square down diagonally...
Barbarian #2 and #3 are bought. #2 takes almost the entire army from Barbarian #1 and the boots and gives part of the army and the boots to Barbarian #3, and he himself runs to defeat Red Hero #2. Barbarian #3 runs straight to the portal (with the boots).
Day 7: A difficult day... so much needs to be done!!!
Barbarian #1 catches up with the last hero #3 of the Red player and defeats him (gaining 10 skill points).
Barbarian #3 (who has the boots) dives into the portal to the Green player and defeats the Green Castle...
Barbarian #2 dives into the portals and collects as much money as possible!!!
In the former Green Castle, 2 Barbarians #4 and #5 are built. Barbarian #3, on the last turn, gives the army, and they, working together, defeat the three heroes of Green (Knight #1; #2; #3). Green is defeated, as is Red...
Mage #1 defeats the Yellow Castle and Yellow Hero #1, who sailed into my boat, after first placing most of the army in the castle (about 25 wolves).
In the former Yellow Castle, Barbarian #6 is built (only 1100 coins left!!!... we take wolves and defeat Yellow Hero #2... Victory...
Result: 4 castles, 2 mages, 6 barbarians... Barbarian #1 gained 10 skill points... there was little mercury... 2 vials were collected, and the second one was reached by Mage #2, who had been running after it with one wolf since day 5!!!

Added 5 minutes ago
Small tricks:
1) I removed the army (archers and dwarves) to slow down the development of Yellow...
2) Mage #1 specifically took 1 dwarf to have a small turn, and Yellow wouldn't run away from the castle further than the barbarian could reach... repeatedly tested!!!
3) Using the arrow keys and the "move diagonally" buttons made it possible to collect some resources, as well as attack one hero, without being able to do so with the mouse!!!:)

Added 5 minutes ago
P.S. You didn't get enough parameters!!! well, 7-9 days is still understandable, but 10 or more!!! in my playthrough (the first one), 21 parameters and 41 mercury were gained in 10 days!!!