KoRn_Dowwg666: And gold and yellow-Gold revives you after you die on the spot, and yellow brings you to the nearest checkpoint after you die. Gold orbs are more expensive but useful...
Hmm....gold orbs? I only thought you can get them from special 'hidden places' (there are only 3 of them). Whenever I bought a gold orb the damn thing transformed into a yellow orb, and basically I had no other source of gold orbs....meh! who needs them anyway :P
The difference between Gold and Yellow modes:
Yellow is the original DMC3 mode. It means that whenever you die during a mission you can retry from the last check-point (and not having to start the whole mission, except if the mission is short and has no check points). The retry is available at the cost of 1 Yellow Orb.
Gold is easier in the sense that whenever you die you have infinite retries (you don't have to buy Yellow Orbs). Even more if you have a Gold Orb you can respawn from the same spot you just died (i.e. you die in a boss fight and respawn and continue the fight, not having to start it all over again). As I said earlier, I could not buy Gold Orbs (they were actually yellow.....it happened a loooong time ago, and I'm not really sure if I actually bought the wrong stuff), and if it's the same for you than I suggest saving the Gold orbs for difficult bosses.