Massive Mushroom island

So i was just flying in creative trying to find a perfect spot to build a military base and i saw this massive island, ive only incounterd a mushroom island twice before and this is far greater than anything i have ever seen. Seed: 2476988882954926932

Edit: I found 2 other (normal) mushroom island just by the big island

Edit: I found also 6 of these water pyramids that is under water and have these guardians and have sponges inside just around the island