No offense to any there, but I honestly believe that the Kill X, X many times challenges aren’t the best challenges to employ. I’ll try and state a few reasons so you can see it how I see it.
It can breed toxic environments. How so? It forces a player to deliberately go out of their way and target X. Player playing X will take note of this and more often than not grow a bit irked by it. Its simply a thing that happens in PvP games, but especially moba-style games. Player using X will feel cheeky and go out of his way to now taunt the other player that is actively hunting them, which in turn will frustrate that player. No one likes to lose, especially if its for a challenge that locks rewards. Likewise, no one enjoys being hunted down and targeted over everything else. Some people actually take great offense to this.
Experienced players who are familiar with these challenges can and sometimes will choose to go out of their way to make sure that the player doing them won’t get to kill them. " I’m ambra and they have Alani on their team? Lol, I’ll make sure to run away the very second I feel like this fight can turn bad". In this game, it can be next to impossible for you to kill someone else that goes out of their way to avoid you, even if it means that they lose. This in turn will frustrate the player trying to do the challenge, they will feel bad and cry unfair. They’ll feel that the challenge was out of their hands, which is a terrible feeling to have when you want to beat X challenge.
Some people will get stressed over these challenges. It simply happens, PvP in general is a stressful environment. But adding more things such as killing a specific character that someone else may not pick or will go out of their way to avoid being killed by you will add to this stress. They begin to play more sloppily and can snap at allies when allies blunder. They’ll take the loss more to heart because they understand they just blew their chance at progressing on their challenge of killing X, X many times.
How would I solve this? Instead of Kill X, X many times, simply change the challenge to Win against X, X many times.
Will people still feel a bit more pressured/stress when they face off against X? Yeah, there’s no changing that for as long as the challenge remains as is, where it wants you to kill/beat a specific character. But at the same time, they can play as they always do. The player won’t have to go out of their way to actively hunt down X. X doesn’t have to worry about being prioritized over everything, so they won’t feel the need to be excessively cheeky.
Its also a lot more simpler and fair of a challenge, ya know? It keeps in the spirit of the game, which is Teamwork. More often than not, Killing X, X many times encourages people to become lone wolves and sacrifice themselves to try and kill X. But if the challenge was simply win against X, then they will be more encouraged to work with their team. Its a great incentive because it means they’ll be one step closer towards completing their challenge.
tl;dr: I advise changing all " Kill X, X many times" Challenges to " Win against X, X many times".