If you read the intro in the Mk3 game, you will find out why. Raiden appears in one part, and the storyline was that he couldn't take part in the fight this time due to Earth being controlled by Outworld Gods. In MKT, he gave up his status as a god in order to join the battle against Shao Kahn. He might have been the one to finally defeat Kahn (him or Liu, but Raiden did fight him), but either way, Raiden regained his god status after the invasion.

But it is interesting to mention that during development they used Raiden's picture on the character select screen to fill in blanks. Also there is a friendship involving him, and when he finally did get added in MKT, he had MK3 damage. Johnny cage, MK2 Kung Lao, MK2 jax, and Baraka all did MK2 level damage. Perhaps they had him in MK3 in early development as a test character...

Very kool.

It would be nice if someone take an interview from the MK TEAM about all that kind of things.

By the way Rayden is in MK 3's Graveyard level !!

Check this shit out :


http://members.lycos.co.uk/murdoink/mksnaps/umk30079.png

can someone explain this mk2/mk3 damage thing to me?

In MK2, regular hits that everyone had (like uppercuts for example) did more damage then they did in MK3. I forget what it was. An uppercut was like 20% damage in MK2 and 17% in MK3 or something like that. MK2KungBroken knows the numbers.

Then, in Mortal Kombat Trilogy, all the characters did MK3 levels of damage, except MK2 Kung Lao, MK2 Jax, Baraka, and Johnny Cage. They went so far as to create the new Johnny Cage and give him MK2 level damage, but then when the recycled MK2 frames for Raiden, they gave him MK3 level damage. And they did a similar recycle of MK2 Baraka, and he did MK2 level damage.