Clearing neutral creatures.

I usually play as a hero, but I start engaging in serious battles around weeks 2-3. The trick with mages in the early stages is that their initial three units seem useless. It's enough to have a couple of chaos spells, enchantment, elemental gargoyles, and magnetic golems, and voilà! We send the golems into the thick of the fight, casting spells on them and the enemies (if there are archmages or nazirs), which gives them +HP and deals damage to the enemy. If we also split the gargoyles into two stacks of 1, we can deflect attacks and increase the power of our spells by 50%, while minimizing losses. It's harder to fight against archers in the early stages, but we can manage with just 40 golems and a fireball or thorns, plus, of course, a substantial mana reserve. By the time they reach us, we cast spells on them, heal, and when they get close, they're killed without any losses. I once used 38 magnetic golems to defeat 76 archers without any losses, instead of using the recommended titans + regeneration. I actually suggest taking thunderbirds; their stats are similar, but they still apply the shooting penalty to both archers and sylvan archers.