Creative the sea level

I tried a variety of ways to make the water look more realistic look make part of an iceberg melting icebergs into the sea in preparation for the later part of the sea under the sea. I hope the sea is not just a plane at the same time there is a depth so I built up two layers of sea level. One of the sea-level will flow simulation when playing the animation, and the other sea-level will rise gradually to cover the mountain, so that when the animation play, it  will not be only a single surface, but deep-sea simulation.

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