Shit, that's in historical setup, not the event.
If Temujin is alive, but invasion starts dynamically, e.g. 1210 start, he gets the same event troops as everyone else.
But after 1220.2.1, he gets "historical troops".
That's a bug.
huh, I always thought it's for balance cos 1220 Temujin starts out in a better position overall. The AI, being stupid, always seem to do better from the 1220 start
besides, 60k attrition-less trooops at least gives the Khwarizmsmsm a little chance to win...