Mega Man X3 Secrets:

Golden Armor: First, X must have all the regular upgrades, hearts, sub-tanks, mech parts, and weapons, but NONE of the chips. In the first Doppler level, after the huge room with the mech pad in the top-right corner, there is a room with some spiked-ball droppers. Slide down the left side of the first pit in this room, and you’ll go into a hidden room if you have full health and everything but no chips. You’ll get a chip that upgrades all of X’s systems (gives him all four chips in one) and turns him gold. HOW’S THAT FOR POWER!

Zero’s Sabre: Of course, if that isn’t enough power, which it isn’t (duh), you can get Zero to give you his sword. First, you have to kill Vile in his hidden factory and have Zero still alive. This can be done by using the Spinning Blade or the Ray Splasher (I think) on him. This will alter the second Doppler level to be much harder. Get to the mini-boss door after the water are, and switch to Zero before going in. He can go through this door. Kill the mini-boss with Zero, and watch, you’ll get his saber. You can use it no matter what you have for upgrades. Just charge up to the green level, and you use the sword just like Zero. If you have the arm upgrade, it will shoot an energy blast. The slash itself will kill non-bosses and knock off half a boss’s life, and the energy wave will take off two-thirds a boss’s life and waste everything in its path.