The phrase "last gen" means the previous or older generation of something, like technology or video game consoles.
Sentences with «last gen»
Something something ports of last gen games are bad something something.... (ludophilelab.com)
Good to see they're not giving it the best on last gen consoles to make everyone happy, saying that its a big let down for current old gen owners. (n4g.com)
I think it's one of the most underrated big - budget games of last gen — considering just how easy it was to get 9's and 10's for other popular titles. (n4g.com)