With this in mind, some nations are much better positioned than others to take advantage of colonizable territory. A formable country is one that does not exist at the beginning of the game (although it might in later historical starts) but can be formed if certain conditions are met.A Reformable country is one that does start as an independent nation but if it ceases to exist, then other countries with similar culture may transform into it, adopting their flag, ideas, and identity. Best African nations I have put about 300 hours into the game so far but I am getting a little bored with playing in Europe. But the convert is a CK2 DLC that essentially makes a custom mod for EU4.