One thing that every player in Rise of Kingdoms should know about is that if you upgrade your commanders using unethical ways, with time they may become useless. In some cases, the situation becomes so worse that you have to create a completely new version, simply just because of your one wrong move.
If you are a beginner in Rise of Kingdoms, it becomes very important to be familiar with this guide, so that you can keep yourself away from such situations.
The very first tip for your Legendary commanders is that you should never use 4-star trick on them. Always keep in mind that rush can cost you worse, so the best way is to upgrade your commanders slowly and accurately.
Here, we will put the main focus on Legendary Commanders as obtaining such powerful and skilled Legendary sculptures is extremely hard and obviously, you would never want to waste your hard-earned sculptures on your favorite commanders. Obtaining other sculptures in Rise of Kingdoms is quite easier, enabling you to fix your mistakes easily. As it is said earlier, not to use 4-star trick on Lengedary Commanders, but you can use this trick on your collected Commanders.
If you are a new player, you might not be aware that each Legendary Commander comes with four main skills. It has the fifth skill as well but is locked, which can only be unlocked after maxing all of the other skills.
In case, if you choose to use 4-star trick to unlock 3-4 skills of Legendary Commander at the same time, and want to upgrade the skills, then any of the non-maxed skill is being picked to upgrade. It may result to the upgrade of the lowest skill, leaving behind the strongest skill. In simple words, when you unlock four skills at once, the chances of upgrading the 3rd skill to max increase to a great extent.
Minamoto is the first skill, which is considered as the most important skill of a Legendary Commander.
Yi Seong-Gye comes as the second skill, somewhat similar to Minamoto.
El Cid is the third skill, or we can say is the worst skill of Legendary Commander in Rise of Kingdoms.
Cao Cao is the fourth skill.
The best idea is to max out the first skill, the most important for your Commander. So, when you have stronger skills in the combat, you will get more advantages, thus can make more damage and more buffs.
Also, if your Commanders are just for gathering and have no chance to activate their first skill, then there is no need to unlock other skills.
Read: best nations in ROK