Let's just say: I am still clueless as to what 'luck' is, or does.
Well, yes, it is as some of you say, eventually, you'll get a 5* through normal gacha, somewhere around a 27% chance on 10-chain.
That was not the point, though, it's not as if I take it as bad advice, or anything.
As for the 5* during events, sure, they're not that hard to get, at least not those now. Found myself someone with a revival skill. Other than that, I need a decently strong team, and a bit of actual luck. Probably not what runs within the game mechanics though.
Neither of which, I have. For the "decently strong team", I'll get there eventually, I guess.