Rating issues
This game contains depictions of arcade-style violence featuring blood and gore. Notably, there is a video showcasing the fan-made Karateka sequel, ‘Karateka: Wrath of Dude’, which features a non-detailed and pixelated human character being decapitated with moderate blood effects spraying out from their neck. Other violence is more moderate and less realistic looking.
Other issues
There are some instances of partially disguised strong language (‘f–k’) as well as partially disguised milder terms (‘s–t’).