Anubis Clicker

Yes. Anubis Clicker is free to play on Steam, so there is nothing to buy to start playing.

The minimum requirements for Anubis Clicker are: Windows 7, Intel Pentium 4, 512 MB RAM, 350 MB storage. It runs on Windows only. The recommended specs are in the System requirements section.

No. Anubis Clicker is a single-player game.

Mostly, yes. Valve rates Anubis Clicker as Playable on the Steam Deck: it runs, but may need some manual setup.

Yes. Anubis Clicker is the full base game. You need nothing else to play it.