Sandcastle is an instant splashback to childhood
I have long dreamt of this game. The elevator pitch is so simple and straightforward that it was an inevitability, and yet it has taken years for someone to do the premise justice. Sandcastle is a sandbox game in the most literal sense - all you do is build a sandcastle as the tide washes in and out, slowly eroding the walls and turrets of your small fortress.
You get buckets, spades, bits of old wood. There is no goal. You are a kid on the beach and nobody is coming to put more sunscreen on you and interrupt your building efforts.
I barely need to describe it any further. You get the entire idea from the video above. There are different types of wall to build (do you like your crenellations in classic or gothic flavour?) along with various sizes of sand bucket, and a bunch of decorative trinkets to save from the waves. Miniature tiki torches, umbrellas, cool shells, that sort of thing. Glass bottles will wash up and you click on them to unlock new building tools, like a handy trowel or a neat little roller that will smoosh everything flat.