[100% Upgrades] The entry in the series that officially ushered me long ago into the Metroid franchise and for good reason. It is one of the few titles in the series that restricts Samus' freedom of exploration to designated and strict objectives which is actually ideal for first time gamers to this series. In this regard though, it also makes the game slightly more challenging to complete below 2 hours with 100% Upgrades for the best ending. Although, this game does appear to introduce concrete objectives in specific areas, it's actually not the first, but may seem that way. Metroid 2: The Return of Samus, was actually the first to do so, using acid/ lava to block progressive pathways and in one instance a barrier before the Metroid Queen's nest until all the Metroids up to a certain point are exterminated. Metroid Fusion is the first title to host the entire game in a space colony rather than a planet, an option that was briefly explored in Super Metroid with Ceres Station! and a little more in the Frigate Orpheon of the jointly released Metroid Prime. Along with Metroid Prime, it is also the first attempt to explain how Samus lost her abilities at the start. To my knowledge, Metriod Fusion has the most Energy Tanks out of the entire series, with a whopping 20 Tanks it is definitely a huge amount; most likely put in place to offset the vulnerability Samus has in her current state to Ice. There is also an unsually high amount of Power Bomb Tanks and it's my own guess that
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