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i guess thats the difference between does and should. Whenever I see x-scissor its pretty safe to assume it doesn't have shadow claw unless im fighting blarajan :). Also your post confuses me, you talk about how its better and kind of go back on it. I dont get it, ahh confusion
its pretty safe to say that X-scissor generally goes over Shadow Claw. whether thats the best or not is a different story, but its easily the most common