i have play n spent not a little diamonds, but until now i never get hero 5*, It looks like this game needs luck in getting a hero if u want to buy hero with diamond. I hope the developer has a solution to this problem because maybe a lot of players will get bored if they are level 29 and above.
You could also try running training camp level 20 to have a chance for 5*. I’ve gotten 2 5*s from it so far.
You definitely should read this topic: What exactly is a Gacha? (Read before posting things about "unfair pulls")
It explains the main idea of this game and helps setting your expectations of the game which is a key point for getting pleasure in the game.
Believe me, not everything is 5 *, there are equally frustrating situations with 5 *. I have mats to upload a multi-colored team of 5 * and I have 5 heroes of 5 *, with one Hotm and only one has received them and only one plays, because I am missing Thorne and the owl to complete the garbage gang. I have 2 kadilen, a quintus and an aegir, and they do not even shade my 4-star team, nor even those of 3. It’s so frustrating that I’m tempted to give the taboos to quintus.