here i totally disagree:actually, fireball shouldn't be a tech vecause that is the omly way to defeat an orc cavalry unit (I forgot name).
- using slowing effect and any ranged units after
- using disarmor spell and killing with any kind of units
- using sacrifice killer spell
- using poisoning
- converting it
- using pikeman or similar anti cavalry units best combining with a spell like slowing.
- using ornithopter or eagle
- any buff on him is removed by disenchant.
in any campaign there can be set any tect to be available or not (as far as i can remember )there is maps in a campaign which is based on the fireball spell.