UDK is $99 upfront with 0% royalty until $50,000. After 50k the royalty rate is 25%. But they have other options depending on what you need the engine for. Unl

UDK is $99 upfront with 0% royalty until $50,000. After 50k the royalty rate is 25%. But they have other options depending on what you need the engine for. Unless I'm reading the license totally wrong. Of course, Flash is not UDK so it's not a fair comparison. Plus, if you use UDK within Flash your royalty rate will be 34% split between Epic and Adobe.