As we know, its Minato's signature move and it serves him good purposes in most battle, however its useless to a foe like Uchiha Madara. Why is that?
-Minato's FTG are mainly on his kunai in which he throws them on the battlefield first
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This allows him to teleport anywhere to those kunai, but giving the amount of power house Madara has, it will be useless. Not only Madara can just create a village sized mokuton:
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But as well as rinnegan techniques:
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And even meteor:
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-Mokuton gives Madara the ability to absorb chakra. That means when kunai comes in contact with mokuton, the marks are absorbed due to them being created from Minato's chakra
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This is proven that when god tree absorbed the mark in Naruto, Minato couldn't teleport to the young Uzumaki:
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FTG will be useless to Madara's mokuton.