A couple months ago Square Enix rereleased one of their gacha games, Grimms Echoes, as freeware.
This is really cool, especially if you're like me and like the idea of gacha games but dislike content being gated behind money or extreme grind, or just hate the idea of the game being cancelled someday and never being able to play it again.
I've been playing it for a couple of weeks now and I'm really enjoying it. The whole game is available for free, forever. It isn't even possible to spend money on the game even if you want to, and the whole game is offline so once you've downloaded it it's just yours. Not a single ad to be found either.
The game itself is a fairly standard fantasy gacha game where you collect heroes and fight monsters, but interestingly it isn't an autobattler; you move your character around in combat and tap enemies to attack them. So it's a lot closer to a traditional video game than most gacha games.
One thing that's really nice about the game is that every character is available in every rarity, so you'll never be faced with a situation where you'll have to stop using your two-star Gretel because she's objectively worse than your four-star Cinderella. (The game is fairy tale themed.) You can just get a four-star Gretel instead. There are also a bunch of systems in place that ensure your pulls will never be horrendous. There's one really interesting one where the game will just hand you a list of every character in the game and let you pick any of them once every hundred hours or so. So if you really like a character you're guaranteed to get them eventually.
The gameplay itself is more or less decent; there are a lot of times where you will just win or just lose a fight because the level difference between you and your opponent is way too big, but there's also a good amount of room to defeat a stronger opponent by dodging their attacks and intelligent skill and item use.
The strategy/character development side of the game is fairly deep, and is the aspect I've found the most interesting so far. It revolves around collecting materials and using them to give experience points to weapons, armor and furniture. Leveling up equipment makes it stronger and leveling up furniture increases the rate at which your characters get stronger when you AREN'T playing the game. It's really satisfying in a kinda Runescape-ish way to run around cutting down trees to help your cute anime girls/boys power up.
The story has been hit-and-miss. The main story has been a bit too melodramatic for my tastes, but I've found the side stories rather endearing. It has a similar feel to Kingdom Hearts's story, so if you've enjoyed that game I think you'll feel right at home.
Overall, considering it's a massive hundreds+ hour RPG with some nice character designs that costs zero dollars and zero cents, I think it's really cool. If you have a smartphone and can read Japanese, or even if you're just interested in learning Japanese, I can easily recommend it. The only other gacha games that've been fully rereleased as freeware that I know of are Tokimeki Idol and Schoolgirl Strikers Twinkle Melodies from a couple years ago. Tokimeki Idol is excellent and Schoolgirl Strikers is decent for what it is, but they're both rhythm games and Grimms Echoes is an action RPG, so for now at least it's a one-of-a-kind experience. I really hope publishers start doing this kind of thing more often; I hate seeing any game die forever and I love getting video games for free!