Tactics for Rampart.

This is actually an interesting question – what's better: focus on destroying the walls to walk through on the corpses, or destroy the creatures behind the walls (with ranged units and magic, luring the besieged enemy out of the walls)?

By the way, based on my (somewhat limited) experience, I can advise you: never forget to fill ALL the skill slots for your hero until you've built 5 levels of the Mage Guild and explored all the available territory.
Usually, I think something like this: at each level of magic, there are key spells for me that determine my further development and tactics:
1st level - Slow, Haste (if available - you need the corresponding magic)
2nd level - Clairvoyance (Clairvoyance is indispensable for diplomacy)
3rd level - Earthquake (if available + earth magic - you don't need a ballista)
4th level - there are many spells here - Prayer, Clone, Portal, Berserk, Armageddon (if available - you need to level up the Resistance skill)
5th level - Dimension Door, Fly, Explosion (if available - air or earth magic is REQUIRED)
Of course, I'm exaggerating a lot; I can't write everything in this thread - it's better to discuss these things over a beer (sorry for the off-topic).