How hot?
Well, being a 40000 lumen light and having 12x XHP70.2s, it must be pushing out about 3400 lumens per XHP70.2.
Knowing that an XHP70.2 consumes 22W at that power level, it means that the light is consuming at least 270W of power at max brightness.
Either it is still going to step down after a few minutes because it is producing the amount of power of an overclocked 8 core CPU consumes under a beefy actively cooled heavily finned heatsink, or it must be running the fan at like 5000RPM to maintain sufficient airflow to keep the LEDs cool, meaning it would be a noise monster.
Cool light though still.