>So yeah, I'd appreciate some feedback on how I can go forward with my game, since I'm getting confused again with it's current direction. I just can't figure out how to make more impacting environmental setpieces (like when in metroid fusion, the game mine is based off, the sa-x blasts through the wall and looks at you).
Subtraction. All the Metroid games do this to an extent, but Fusion really capitalizes off creates tension be taking away Samus's abilities and giving them to her foe. Same goes for the end sequence in Zero Mission, and to a lesser extent the end of the power bomb sequences in AM2R.
I don't know what vibe you're going for, but consider limiting your character's options. Give them an ammo count, have a pesky enemy steal their gun, have them have to escort someone. Maybe say the energy field their power-suit's barriers emit radiation and you don't want to destroy the precious item or hurt your fragile NPC. Cause you know, if your character is all powerful, you have no room to create challenge or growth.
With that said, you might want to tinker with changing the core mechanics too. Note the only metroidvania that's mechanically close to Super Metroid is Axiom Verge, and it still limits movement speed and transversal options and replaces the most powerful powerup with subversive/world bending ones. It's case there isn't much room for designing interesting combat situations or even platforming situations in Metroid, because well, Metroid isn't a game a about combat or platforming. Those things are supports to Metroids core engagement: exploration. It's the reason why the final upgrade in the game is basically flight, now you can go anywhere and destroy almost anything that isn't a boss or a laser beam.
If you're gonna continue with this project without reducing/changing your combat options, you'll need to develop an interesting world to explore that's aesthetically different from Metroid, or plays with and/or develops upon Metroid's world design language.
By world design language I mean stuff like, you see a crack in the wall? Shoot/Bomb here. You see a space that too small to fit in? You'll need an alt form or another body.
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