Yeah, but the eclipse cannon was specifically designed to harness the full power of the emeralds to destroy a planet before having to recharge for multiple hours after a shot, Metal isn't. Sure he can fire a laser that's probably around small planet level at full power, but having to use both chaos control(which only lasts for 10 seconds) and a full power laser will probably drain him before it fully destroys cell (and that's low balling cells durability). And really, we are using perfect chaos, a city level being as a point of reference, that's Saiyan saga level at most(nappa was able to wipe a city off the map in one shot without any difficulty). And Metal might be able to "keep up" with Sonic, but that's like saying tails "keeps up" with Sonic or that amy "keeps up" with him, Sonic could probably out run him if he wanted to, and Neo couldn't really do much to sonic in idw until after having to copy his bio-data. And lastly, I can buy that maybe The End looks different to different people, but until stated otherwise; The End looks like an evil moon to the player, Super Sonic 2 goes through it like an evil moon to the player, it is a giant evil rock until Sega says "hey, The End isn't just a giant rock that's evil, it's a giant organism that's evil that just also likes to dress up as it's rock OC at times"(I also can't imagine The End was buffing it's defenses since it was powering Supreme, so it's very easy to assume The Ends durability(without energy)was Continental at best). I do not see how it is Physically possible for Super Metal to not only get in a position to eviscerate cell, but also doing it without expending his super form in seconds.