@Kamelpov I meant the mongol's opponents were unfamiliar with it, not the mongols themselves. The MC's opponents would be familiar with forest combat, so that advantage is gone. Also you're 100% wrong about "no well developed tactics" because the ones doing the tactics are modern people. It's about how much the player knows about tactics. And 'common teenagers' can be very infomred about tactics because they have this thing called the internet. Look at how much random people can learn about guns just because it's something they like. Just because they don't have advanced technology doesn't mean they can't use advanced tactics.(that's exactly what the MC does).
Your entire argument is that "MC is better at strategy than the bad guys" but if the MC isn't then he's screwed. And he doesn't -know- that he's better than them, so tactically it's a horrible choice to rely on that. Also for the record, the majority of medieval combat didn't happen in forest like movies want you to think. It was in wide open plains. Here's a post that explains it. https://www.quora.com/How-did-medieval-armies-battle-in-forests
Your entire argument is that "MC is better at strategy than the bad guys" but if the MC isn't then he's screwed. And he doesn't -know- that he's better than them, so tactically it's a horrible choice to rely on that. Also for the record, the majority of medieval combat didn't happen in forest like movies want you to think. It was in wide open plains. Here's a post that explains it. https://www.quora.com/How-did-medieval-armies-battle-in-forests