That is pretty normal for playing games, especially if playing them for long periods.
NOTE: Only do the following if your laptop isn't under warranty. If it is, then I would suggest contacting the manufacturer about any overheating.
You can try cleaning out the interior of the laptop. Remove dust, debris, etc. Making sure to pay close attention to fans and vents. Just be careful you don't damage anything inside. Should this not make a difference (of if it is clean) then the next thing I would suggest is replacing the thermal past.
Also, make sure the laptop always has good airflow.