User blog comment:Lord Loss/Monster Hunter Frontier G Discussion/@comment-108.202.190.251-20130425235602/@comment-4009941-20130426061710

The GR ranking system goes like GR1-1 Rank up 1 monster unlocked GR1-2 rank up another monster unlocked GR1-3 Rank up to GR1-4 and urgent for GR2-1

As for update seosons they seem to be called G1, G2 and on to remove peoples confusion