In the early reveal trailer for generation zero the game had a pegi 16 rating
Which using second extinction as an example would’ve likely given the game an mMature rating
After the launch trailer released the game had a pegi 12 rating
I’m just curious as to what changed in development that dropped the rating
Care to link that trailer? 
Since i looked it up and it has ESRB Teen (T) rating, not Mature 17+ (M) rating.
Early reveal trailer, 10 months before release:
Here’s what those ratings also stand for:
ESRB
Teen
Content is generally suitable for ages 13 and up. May contain violence, suggestive themes, crude humor, minimal blood, simulated gambling and/or infrequent use of strong language.
Mature 17+
Content is generally suitable for ages 17 and up. May contain intense violence, blood and gore, sexual content and/or strong language.
source: ESRB Ratings Guides, Categories, Content Descriptors
PEGI
PEGI 12
Video games that show violence of a slightly more graphic nature towards fantasy characters or non-realistic violence towards human-like characters would fall in this age category. Sexual innuendo or sexual posturing can be present, while any bad language in this category must be mild.
PEGI 16
This rating is applied once the depiction of violence (or sexual activity) reaches a stage that looks the same as would be expected in real life. The use of bad language in games with a PEGI 16 rating can be more extreme, while the use of tobacco, alcohol or illegal drugs can also be present.
This is the reveal trailer
That trailer starts with the “pegi 16” rating
If you look at trailers from release onwards it’s a “pegi 12” rating
So apparently something changed in development
Also regarding M ratings
I was using second extinction as a basis
Second extinction has a pegi 16 rating in Europe and an M rating in the west
The trailer begins with “Provisional PEGI 16” rating. Meaning that the PEGI 16 rating wasn’t set, instead, it was estimated.
It’s like when you estimate your car repair bill to be €1000 but instead, it turns out to be €500. Which then saves you a lot of money. Or in game’s sense, it opens game for wider audience (ages 12 and up, rather than 16 and up).
Alright I see, I’m American and I’m more accustomed to the esrb and they have an entirely separate rating for unrated games being rating pending