You might have heard other Commanders talking about the Mega Crab.
The Mega Crab is an enormous purple, crab-like machine created by Dr. T as a weapon of mass destruction with which he tries to take over the Archipelago.
Once it appears on your map, you will have to defend the Archipelago by beating as many Mega Crab stages as possible. Naturally you will be well rewarded with resources and not to forget: fame and glory!
It is unknown when the Mega Crab will appear next as it is not a part of the regular Event Cycle.There is no set schedule for when or how often the Mega Crab will appear – so you better be prepared at all times!