Gantz is a death game where people are forced to to kill. So the premise is similar, although the setting is completely different. One is fantasy, while the other is sci fi. being a game, SOA doesnt have any actual gore, while Gantz is more mature with both gore, and mature content. If you like one, you might enjoy the other if you want to feed on some misery in different forms.
It's baffling that Overlord wasn't recommended here, perhaps because there's a large amount of spin-offs for sword art, nevertheless i will fill the void here. Overlord is about a person that lives on inside a world that started out as a game, but became something more, if you enjoyed sword art, you will definitely love Overlord.
These two manga's are a peas in a pod. A strong player living and fighting In a VRMMO as if it was real life, unable to log out. The similarity is outstanding. Yet The New Gate shows a totally different story right from the first chapter, if you enjoyed one, you will definitely enjoy the other.
I feel that a lot of people who have read Sword Art Online will like No Game No Life, not really because they are very similar, in fact they are two ends of the same shelf so to speak given that one is about tying to escape from a new world and the other is about making it in a new world, but the key similarity is they both feature a main character who enjoys games and uses that to pursue their end goal. So in conclusion they are both rather different whilst being subtly similar given they are both about someone who gets a fresh start on life in a world which rather than makes them outcasts due to their skills and hobbies makes them more important and I feel that's one of the main reasons people read things like this because they identify with the characters and enjoy the idea of a fresh start. read more
Both have similar feel as a dark reality of death that hang over the peaceful lives of the characters. The protagonist in SAO is also very similar to layfon as they are both socially awkward, are self-critisizing, have a dark haunting past, and extrememly overpowerly strong.