The developers choice to not let you freely switch between, without destroying the last equiped idol, is a bad choice. Especially considering how hard they are to get.
Even if you clear all 3 bosses it is not guaranteed that you get an idol, and much less likely you get a usefull one. On top of that, units will sometimes be changed acording to balance the game. Mind you, I am not criticizing them for changing units, not at all. But that do mean, that you will end up, with a strong Idol, on a unit you will no longer use. And I think that is a poor game design choice.
I got a single +1 streng and ability idol, I am considering given it to Rock G, but I hesitate because I find it likely that he will be nerfed in the future, so I have a strong Idol, that I don't know what to do with, because I do not want it to be wasted.
Image playing another game where you collect gear. The joy about earning said gear, is that you can use it immediately, and see what differnce it makes, and if you get something better , or it did not work the way you'd expected it to, you can allways change it, without destroying it. Now image a game, where you would hesistate to even don the new gear, even though you know it is better.
So to recap. I think the choice not to be able to freely switch between idols is a really bad one.
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