https://youtu.be/NKSw7nOVkU0

I asked this for like 1 month and later I failed to change Mario's lava scream cause it's included with the smoke sound and I can find it nowhere. Newer changed Mario's burn scream as well, so allow me to change it for my hack that is gonna release in the future please.

sound_data.sdat > WAVE_VS_SE.swar > SWAV 3 (Mario) and SWAV 4 (Luigi) are what you should be looking for.
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Object reference not set to an instance of object is what I get when using the exact WAV file to replace his voice.

You need to extract the SWAVs 0-2 (and optionally 4 if you want to keep Luigi's voice), convert the new Mario voice (which will replace SWAV 3) and new Luigi voice (SWAV 4) to SWAV using wav2swav, and re-pack the SWAR using swav2swar.

Do not directly replace the SWAV in Nitro Studio 2, as it'll break the other sounds in-game (though they'll play fine in NS2)

Then you can proceed to replace the SWAR in NS2.
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I'm late, but which software to extract? I have Audacity to combine the scream and the smoke from the game

You can extract the SWAVs directly or as WAVs in Nitro Studio 2.
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