Okay lets look at Raiden in MK1. He really wasn't there to help the earth warriors, and you can tell by his ending he had evil intentions, but those intentions never fruited (gay) as Liu Kang won the tournament. Now think of this. Why did Raiden not interfere before Liu was killed. I'm sure an elder god would know of the use of a portal known to elders and dieties. Now comes MK6. There could be a huge number of possibilities. Raiden could fake his death (how shocking would that be?), he could end up killing the dragon king right before you defeat him (if you play him), or heck he could turn out to be the dragon king, and the reptile thing could just be a ploy (imagine the in game intro when you finally see him, he turns around and its revealed to be raiden. Out walks Shang Tsung and Quan Chi!). This could definetly be a huge deception.