How to win with a “weak” Knight?

I was just playing as Necropolis with Mountain King on a King map, and I didn't do very well, finishing in 18 days. I couldn't create the same kind of chains as you did in the tournament; I only managed to get to two castles by day eight, but I had a good army (I tried to rush to the Wizard with 17 Boars and 14 Skeletons, but they stopped me; I only managed to defeat the Sorcerer thanks to about 50 Orcs and half a hundred Goblins). It felt like only a week had passed, but it was already getting tough. I continued on, with 50 Boars, 7 Wraiths, 50 Goblins, and 25 Halflings. And then, on day 11, I was attacked. It was the Barbarian, who somehow already had 10 Trolls, 12 Ogres, 80 Goblins, 15 Wolves, and 50 Sprites. A very unbalanced army. I had to pay them off. And then, Cyclops started showing up. In general, the computer-controlled Barbarian is usually the worst, even worse than a Warlock with a large army and high spell power. And those weak Wolves aren't that easy to kill. And considering that Beavers often have Leadership and Luck, if you don't have a powerful hero with even better stats, you're in trouble. I remember once, 10 Chieftains with Luck dealt 200 damage to my Titan. By the way, in my own castle, I couldn't build Vampires in the first week because the path to the Lumber Mill was guarded by almost fifty Centaurs, and they wouldn't let me pass, and I didn't want to waste ten Orcs on them. If I were playing as a Knight, I obviously wouldn't have even built Swordsmen. And if it weren't for the neutral creatures helping me, I would have failed the scenario 95% of the time. In Good vs. Evil, I put Paladins on the first week on Impossible difficulty, and headed towards the Warlock. The Warlock had a decent army, including Hydras, and he didn't let me pass with spells. I don't remember what I did then. But it's not that easy to get Dragon Riders as a Warlock on the second week; you need 30 Sulfur.