Ending Diagonal Triangle pattern occurs only in wave (5) or (C) of any impulse let it be a wave bigger wave (5) or inner wave (v) of any degree. So whenever you are observing something like ED, you need to make sure that there is wave (1), (2), (3) and (4) before the start of this pattern because ED cannot happen anywhere, it is always a wave (5) The ending diagonal is a special type of wave that occurs only in Wave 5 of an impulse, basically, it indicates the termination of the trend. It consists of 5- waves labeled 1, 2, 3, 4, and 5 where each wave is a 3-wave sequence and wave 1 and wave 4 overlaps each other.