This project is part of the electronic boardgame that I'm designing (https://hackaday.io/project/171734-interactive-cell-board-game), but could be used to interface the RPI zero and connect it to other peripherals.
It has an 1.3" OLED SPI display, navigation buttons and RGB LED's to show the player status and the current game phase.
It's is supplied from a connector that it's wired to the boardgame, but really only needs 5V. The boardgame will be also connected by USB to control it.
It also has another connector with supply, SPI and I2C to interface to another board as a second player interface or to an NFC reader that could be used to read a tag in the game pieces.