In terms of playing the longest, I was quite into both Cookie Run: Ovenbreak and Cookie Run: Kingdom. I found the characters very cute, and the storyline can be quite interesting (at times). But I stopped playing Ovenbreak after getting bored of the grinding, and I mostly play Kingdom because I have a guild to handle. I still love the characters though.
Sky: Children of the Light is also a fantastic game, the story and the art is very memorable, I really loved how beautiful the ending is. I especially loved the flying mechanic, I love the feeling of flight and speed, this game might have inspired me to create my most favourite OC Cosmos. Not only that, it is a multi-player game that strangers can help each other out during quests, you might be lost or wandered into danger, and some random person might give you a hand!
A game that I haven't played in ages, but has a special place in my heart, is Deemo. It is a rhythm game with a touching storyline. It also introduced so many songs and musical artists to me, like Mili.
I see so many people who also played the games I like in this post, that's nice :3