Indie developers should take a good look at Exo-Calibre as it can provide a very helpful lesson: a video game doesn’t always need a high complexity or seemingly endless content to be enjoyable. This shoot ‘em up, which looks, feels and plays as if it came straight from the ‘90s, manages to be one of the finest in the genre. Without introducing a new mechanic, focusing on pleasing a niche hardcore crowd, or having tons of unlockables, Exo-Calibre is simply fun to play - and sometimes that’s all it takes.