I have a good 4 star Felicia and Olivia,(This is mainly focused on Felicia) and like both units a lot but i often find myself spending feathers on other characters to get them to 5 stars and there is never time for them truly, how viable is it to merge them at the 4 stars and use them in the arena every now and then? Should i better wait?
If you have at least 6 of the same 4 star unit (which I doubt you have, you don't seem to be a whale) you can create a 4 star unit with +5 level, which gives you the same BST as the unit would have as a vanilla 5 star version I believe. So while you don't need to 5 star units to make them good, it takes a lot of merging to make a 4 star unit just as good. No easy way around it sadly
If you never plan on making a unit 5 star (or at least not any time soon) I'd say merge the 4 stars. I have a 4 star level 40 Gunter. He's my best unit but not the best unit ever. I don't plan on ranking him to 5 stars but the level boost makes it so he's usable, rather than having a bunch of Gunters I don't use. Depends if/when you wanna make them 5 star.
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