In the second game, the special structure in the Warlock castle actually produces an extra 500 gold a day, just to balance out the cost of the troops. In Heroes 1, better find a gold mine, or a gold-producing artifact, or conquer another castle. 🙂
It’s interesting you say that because I’m on level 4 of the campaign now, playing as Knights, and I’ve run into a difficulty wall where I had to admit defeat and start the level again – I spread myself too thinly with units that get torn through like paper, and I’ve been pining for access to the more powerful units of the Warlock class! Does the increased cost of the Warlock’s army make it impractical to build it up in the early game?