Are mongols supposed to appear with 17 stacks?

[FactionHeir]

45
How much land do they hold in your campaign that they can afford to buy all these

Mongols and Timurids aren't supposed to be a "kill a few stacks and that's it for them" thing anymore, they will kinda like historically be a great menace that will take some effort to beat back.

Its a lot easier to kill them before they manage to carve out an empire, because then you essentially are up against a player like yourself, just that they aren't quite as smart, but got quite a bit more firepower than you.

The way I play it usually is to not build huge stacks until the time I actually receive the Mongols spotted message (to make it fair I suppose). That's usually a cue to start massing your armies and prepare to go to an extended war. And yes, you do need all your castles and cities to be on high alert and you can't really rely on 1 or 2 stacks produced in ME to take care of it all. A bit like a crusade

Nevertheless, let me know how you get on. If its really too difficult, I'll tone them down a little bit.