Is there a requirement to enter the last chapter?

Entering the Portal to the Eye of Eden requires a minimum of 20 winged lights in your possession before you can enter -- which you would most likely have even by just playing the game normally. However, in reality, you would want to have something far greater than this value, as they would serve as your hit points in that chapter, and a form of currency to have them exchanged to ascended candles upon completing the final phase of the last chapter.