I'm guessing that you're talking about Mononofu. In that case, my answer is, I don't know because I've never had one. I'm not sure if it's even possible to complete them yet. In my inventory, I have 15 of shard 1 and 6 of shard 2, but I've never seen a shard 3, nor even any fight that looks like it might drop them. My recommendation would be, just push generals to four stars and don't worry about it.

Of course, that nearly guarantees that next week will be an event that gives you 10 EVO emblems and you won't be able to apply them to four star generals. (No, I'm not aware of coming events.)