刀剑神域：失落之歌

The story line is short and skill system is not flexible as SAO:Hollow fragment. BTW flying system is really cool after you unlock the height limit.
POS:
Can use different character (10+)
Cool flying system
Fluency of sword skill is better
No Game Over when AI dead
Can take 2 teammates to adventure

NEG:
Unbalanced weapon attack power
Skill system is not flexible(No OSS skill combo like SAO:HF. OSS in LS are like normal sword skill)
Air fight is hard to control
Short story line
No exp for side quests

Compare to previous Hollow Fragment,this time do add more staff sort of Aerial Battle,4 big map to discover & you can choose your lovely series females character besides Kirito & your own created character.