Favorite gacha game/app?

So playing gacha games became quite the trend latly, and even some companies started releasing gacha-type of games for their growing popularity. Among them, there's Genshin Impact, which is one of the most popular gacha game as for today!

I'm F2P, but I grew a big love for gacha-type of games, and play Genshin, even Cookie Run, all sort of Anime-like gacha type of apps and more.

What is your favorite gacha game and why do you like it? Let me know!