- A reference guide and manual in Russian for Heroes 3.

What about Kira or Brissa and their specialties? Does this also apply to all heroes whose special ability is a first-level spell that doesn't deal damage?

The Haste specialist adds a bonus when using the Haste spell.
The Stone Skin specialist adds a bonus when using the Stone Skin spell.
The Bloodlust specialist adds a bonus when using the Bloodlust spell.
The Accuracy specialist adds a bonus when using the Accuracy spell.
The Weakness specialist adds a bonus when using the Weakness spell (bonus to reduce creature attack).
The Prayer specialist adds a bonus when using the Prayer spell (for all increased parameters).
For level 1 creatures: +3 units
For level 2 creatures: +3 units
For level 3 creatures: +2 units
For level 4 creatures: +2 units
For level 5 creatures: +1 unit
For level 6 creatures: +1 unit
For level 7 creatures: +0 units
A hero with the Executioner (Dragon Slayer) specialization adds damage to level 7 creatures when using the Executioner (Dragon Slayer) spell. The numbers might not be entirely accurate.
For level 1 creatures: +20%
For level 2 creatures: +14%
For level 3 creatures: +9%
For level 4 creatures: +4.5%
For level 5 creatures: +0%
For level 6 creatures: +0%
For level 7 creatures: +0%

P.S. The situation with Adel is unclear...