[quote]How did the forward into dawn magically change shape between 3 and 4?[/quote]It technically still looks like it does in Halo 3. It's visual change is the result of artistic licence. [quote]Why are there many spartans with John's armor in the opening of halo 4?[/quote]Chief's armor is based off an earlier model of Mk. IV. The other explanation is that they were using assets and the prologue is not entirely canon.