Timothy scavenged 100 LEDs from a Christmas lights and decided to build something interesting. So he took PIC12F629 and soldered a dual dice schematic on prototyping board. Since PIC is in DIP8 package it means that only six I/Os are available. One is already required for button input. In order to have two dices working special wiring is needed.
After short analysis it is obvious that LEDs on dice lights in pairs except center LED. So three pairs and single center – total four pins for single dice. But there are two dices so fifth pin is used to drive pair of transistors NPN and PNP that simply toggles dices at high frequency. So all you see is two dices working at same time.