@Nasafitra I don't think there is anything in current main line game can kill him naturally except Fatalis.
So if not Fatalis it's probably new final-final boss.
@BannedDino I think Namielle is more fitting to scarlet Forest.
Chameleos is more of a dense and humid Forest lurkers not flooded one.
But if King of the sea can appear in fresh water biome, I don't doubt that it is possible.
@peagade__ CAPCOM in recent years did trying to go outside their comfort zone.
But
Exoprimal - Actually good designs wasted in the wrong genre.
Kunitsu-gami - Great but too niche.
Pragmata - Hell yeah.
1/3 hit is actually impressive, but time&money wise it's not so great on paper.