Uninvited guests.

The computer didn't choose anything itself. It picked up a sword first, then found a staff. Usually, the computer can't change an item from the inventory to be held by the hero.

Right now, there is a vote for the best map of 2015-16. If you want, you can support your favorite works here.

Just in case, I will repeat that with flagships, AI won't receive artifacts randomly. At the start of the game and with each regeneration, the AI receives a random set of artifacts to enhance its abilities. If these artifacts were given to the main hero - the player - as if from a cornucopia after every victory, it would become, IMHO, not interesting to play

Added after 1 minute
Unfortunately, there is currently no time to work on improving the specializations of humans and necromancers. Suggestions from players are welcome.