Once Mongols get up to castle age with a Steppe Redoubt, for example, if the food's already present, they're going to be getting so much gold in and it's kind of crazy just how explosive the army can grow.

Mongols typically in the late game are known for their Mangudai as one of the best late game units. However, if any civ can deal with it, it would be those Yeoman from Lancaster.

Demilancers don't poke the same way Keshiks do. Keshiks heal, and Demilancers aren't great at soaking up damage. They have no chance against Keshiks — it's like horsemen against Keshiks without the move speed. They won't win that fight, even with Call of the Nobles, which is why they need the padding of a knight.

Improved Biology costs 1500 stone and gives Keshiks an additional +10% health, totaling +35% extra health, making them very tanky.

Earl's Guard move a lot quicker than normal Men-at-Arms. 1.25 tiles per second movement speed compared to 1.12. So they're able to keep up with villagers running away as well. Though with Deer Stones and Wheelbarrow, Mongol villagers are also fast.