Seriously I didn't know this movie was based on a game with the same name. Okay let's go straight to the point. This movie is like those Sharknado, Piranhaconda, Spider monster kinda TV movies you know. But Rampage put Dwayne 'The Rock' Johnson as the main actor and suddenly it's a Grade A movie. Yes the CGI is great compared to the TV movies but the idea was pretty much similar. The jokes in the movie didn't quite land and it seems like it's forcing the characters to throw some jokes. Aside from The Rock and the monsters, other characters are so stiff and I almost cringe watching them.
However, it's still a fun movie to watch. You know that guilty pleasure? yes this is the movie. Story wise I'll give this movie 2.5/5 stars. It's all kinda been there done that and you can tell the story without even watching it. My favourite monster is definitely Monster Croc.
P/S: I should look for the game, it must be fun destroying cities!