Posts from What is Training and how can you counter it? Auto-translated

Okay, let's say they really did limit him to 20 creatures (this isn't an expression of distrust, I'm just saying it that way). With such a limitation, you can't create a lot of archers, but you can create a lot of Knights, and Inquisitors will be a very good addition to increase the number of Knights. So, training strength is still important.
To Lord Vampire:
of course, he's not as scary compared to raising the dead in Necropolis cities, for which they don't even charge money. But this is much tougher, and you can fight against training in this way.

when playing as Isabelle, you can freely convert peasant units into Knight units.

I don't see any problems with this training; it's very expensive, and the Knight won't have enough money to upgrade everything, but in the end, you're not playing against Bill Gates. The only time the training really hindered me was in the "Triumvirate" mission, where Isabel created 600 paladins. It's also possible to fight against legions of skeletons. I think the most difficult thing is fighting against an Experienced Dwarf, because he has two types of magic: regular and runic, which are significantly cheaper than the training.

A player who is good at developing on the map and earning money with two heroes can easily use the Training ability, as long as the map isn't too poor. As for the computer opponent, it's not the best ability, but compared to how it uses Avenger, it's still decent.