Social Pyramid Scheme

You get a bonus for inviting your friends and then they have to invite their friends.

Some games will give you a bonus when you invite your friends to play and link to them to your account. This bonus may be a one-time benefit, or it may be an ongoing benefit that improves the gaming experience for each friend that you add. This gives players a strong incentive to convince their friends to play. Those friends then have to sign up more friends and so on, leading to a pyramid scheme and viral growth for the game.

Often, this is combined with another Dark Pattern called Social Obligation where you and your friends can help each other in the game. This leads to a feeling of obligation and people keep playing the game even when they no longer enjoy it.


Examples

Tiny Tower Tiny Tower
"There are levels of benefit for getting more and more friends hooked (to a point, I think; I've never done it)."

Coin Master Coin Master
"You get more coins, spins, etc. when you invite friends to play"

War and Order War and Order
"Referral rewards"

Fishdom Fishdom
"you get free stuff for inviting people"

The Simpsons™: Tapped Out The Simpsons™: Tapped Out
"adding friends is a mandatory quest, and interacting with friends enough times earns you exclusive rewards."

Star Stable Online Star Stable Online
"there is (or used to be) a feature that allows you to gain rewards for inviting a friend and getting them to level 10 (which in itself costs money, unless given free membership at the time of creating the account)."

Peridot Peridot
"Breeding Peridots is much easier with linked friend accounts. There’s a lot of pressure to friend strange in order to breed your pets"

BitLife - Life Simulator BitLife - Life Simulator
"If you want to post on social media, share this app to someone!"

Figure Fantasy Figure Fantasy
"At some point the announced a limited time offer for inviting back old players who left the game."

Hitman Sniper Hitman Sniper
"you get a "free" sniper for inviting any friend"