The Combo X Saber.
First try the saber button. If it works, press triangle and circle button(dash button)rapidly. It will be more faster. And off course, it is good against the Nightmare Zero. However, avoid using the Rapid Fire Part that will effect the performance. Also, you can't use the Shadow Armor. If you do this, you hand might get tired. So, if your are a beginner, use Slower Motion (change at the option menu)
If you need more help, we've got more Mega Man X6 cheats and also check out all of the answers for this game
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