Devil May Cry 4/Bosses

Before we begin, there are a couple of rules you should know:
 * 1) With Nero, when using your "buster" move against a boss, before using it, turn on devil trigger. Because of the animation used for the move, if you turn on devil trigger before you use buster, and when the animation starts turn it off, you use a more powerful buster move (as if you were in devil trigger) but do not drain your devil trigger.
 * 2) When in a boss fight, or any fight for that matter. If you are in a hold where you cannot move or are taking constant damage for a prolonged period of time, turning on devil trigger provides about one second of invincibility where nothing hurts you, and you break out of an enemy's grasp

Dante Boss Fight
In either fight against Dante with Nero sure you could technically use a fair tactic, or you could you the easy way. With Nero against Dante you can just continually fire your gun (Blue Rose) then once you get close enough to him, buster. This technique may be a tad difficult to get used to, due to the distance you need to be away from him, you can't be too far away, but if you get too close he uses his stinger move.