You can unlock them from the view unit screen. Select the unit you want to fuse, and on their detail screen, simply click the lock and it will unlock them.
thus, How do I increase my royal rank in Wotv?
By completing the record mission “Clear Chapter 1, Scene 1 Prove Your Worth”, you will get 300 Royal Points. This will allow you to reach Royal Rank 1 and unlock the 1.5x Battle Speed function. You can also get 10 Royal Points per day by obtaining 100 Daily Mission Progress Points.
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