Change a game to F2P
Nowadays, more and more studios are focusing on F2P mobile game to make more money. However, it may be difficult for them to transform a famous game into a F2P model because they have different design goals so that not every successful PC or console game can become a successful F2P mobile game.
Getcha system is a very simple system that almost every F2P game will use this feature to collect money from the players' pocket so that usually the game designers will give additional value to items so that the player would like to use getcha system to get them. For example, the FGO players will want to getcha some certain characters because of the CV they like, the picture they like, the story they like or the ability they like. On the other hand, designers usually use time-limited getcha system to collect more money because when the player knows that this item will not appear after a long period or forever, this setting will definitely change the decision-making method and give the money to the game directly. I think there is some consumer psychology involving in the getcha system design so that they can successfully sell data to the players and receive massive money.
Payment moment is a very significant part in the F2P game so that when game designers are designing those systems, they need to figure out how to implement payment moment into those systems which means they have to leave rooms for the money. For example, in a P2W(pay to win) MMORPG, usually the designer will design a feature that after you were killed by the other player, you can pay some currency and rebirth on the same position with some stronger buff so that you can fight back. So usually the normal design is after the player died, they will get the rebirth on a safe area like a town. However, they will design some privilege from the normal system and they also need to think about how to sell those privilege mildly. There was a saying in China shows that people will not hate they have little, they hate they only have nothing. So that usually the designers will design those privilege with two aspects so that they can keep the poor players playing and serving the whale better.
The biggest differences between a normal PC/Console game and a F2P game is that when the player is playing a F2P game they are playing the game with many other players so that the social activities will influence how the player plays the game or pay the money. So that those game will use leaderboards or skins to show the status of the players so that the players will want to use the money to buy status which is exactly how people do in the real life.