We must not forget the 2 Atari 2600 games that where Branded as "too violent" and where put behind store counters and where only available to buy if someone asked for them. Halloween & Texas Chainsaw Massacre.
And of course we must not forget the games that started games being rated.
Night Trap (which really isn't gory)
and Mortal Kombat. (remember how Genesis you had to use a code to see blood while SNES edited all the gore out and made it fail.)
And we must not forget Doom and Splatterhouse.
Chiller and Death Race where released (poorly i might add) to the NES.