Raiden gotta few.
forward punch into forward kick into forward special
Also you got Uppercut into Down special into uppercut again into forward special
Viewing post in Mortal Kombat II: The Web Warriors comments
Thanks for the feedback!
Some of the combos are explained in the tutorial section (there are general tutorials and a specific tuto for each character).
If you get the opponent in the corner the combos can become even nastier. For example with raiden you can do huppercut into down special into hupper into forward special cancelled by a wavedash into again an other huppercut into a back special.
Also, combos with mileena can be almost infinite if you get them in the corner and have max ammos on your knifes (I think she's the best character, or at least the most difficult cpu to beat).
Subzero has a worse kombos than raiden but has way better defense as his ice flask can make him very hard to approach and any obvious attack can be countered by his down special and lead to a full combo (and he has a bit more hp).
I don't guarantee the game is really balanced though but its not an esports lol.