Did a quick playthrough using these 2 codes. My findings:
NLKA-CA2J
Invincibility (you can walk thru enemies).
- The green highly toxic looking water in the sewer level still hurts.
- Projectiles still hurt. This includes bullets, Venom's webbing, Electro's bolts, Hobgoblin's pumpkin bombs, and the robots and lasers in the Caverns level.
AKKA-CA5C
Some enemies don't move. This includes the dog, rat, thug, snake and Lizard.
- Also works on Electro (in a way), he can only move up and down, and can't come towards you when walking away.
- Also works on Kingpin! This is very welcome! :)
- Needs to be turned off after defeating Kingpin, or the ending cutscene won't play out. The code applies to all characters in the cutscene, including Spider-Man.
edit: It also affects Spider-Man in the cutscenes between levels.