Here is the full list of all 20 RUGBY 15 achievements worth 1,000 gamerscore. It takes around 4-5 hours to unlock all of the achievements on Xbox 360.
Successful lineout throw by human-controlled players on same team
Win 10 matches in a row, vs CPU (Hard) as the lead profile
Get awarded two yellow and/or red cards in a match
Do not concede any penalty infringements in a match
Punt into touch for a territorial gain of 50+ metres
Score a penalty goal or conversion from 55+ metres, vs CPU (Hard)
Score a try after running the ball directly from behind your own goal line
Score 10 tries in a match, vs CPU (Hard), 10 min halves
Score a drop goal from 40+ metres
Score on 5 place kick attempts in a row during a match, vs CPU (Hard)
Score four tries in a match, vs CPU (Hard)
Run and score a try directly after breaking out of a tackle, vs CPU (Hard)
Score a try
Win the PRO12 title
Win the Pro D2 title
Win the TOP 14 title
Create and win a competition in Custom Cup featuring 20 teams or more
Win the AVIVA Premiership title
Win a match against an international team rated 90+, vs CPU (Hard)
Win 5 ruck turnovers in a match, vs CPU (Hard)