The mission portals can be used to send your bots on missions to retrieve all kinds of exciting treasures. You can check what kind of prizes are available at each mission before starting the mission. Each mission portal can be expanded with gems so that you can send 1,2 or 3 different bots on a mission at the same time. The more you send, the higher chance you will get to unlock all the presents at the end as the prize depends on how well your bots did on that mission. You can also send pig reinforcements to reduce the time that the mission will take.
At the end of the mission, you can unlock presents to receive different materials and other prizes. The materials are needed for upgrading your bots but you can also use them in the Professor Pig's Lab to craft Energonicons, gems and coins.