Any idea for entertain 2 yrs old boy on the plane? 10 hrs flight!!!?

If you have a portable DVD player that will also help on top of the new toy idea. I have heard of people giving their kids benadryl to mellow them out and make them sleep. I am not in agreement with doping up your kid but it is a choice. make sure you bring something chewy for take off and landing to help his ears pop. 4 hours at an airport can either go fast or really slow I suggest making him walk around the airport with you as much as you can get him to, this will help him want to sleep naturally on the flight.