5 Boosters and you have Grimlock. Me: Over 100 Boosters (2 sealed boxes + assorted packs at various stores) and still no Space T-Rex. Granted, I have everyone except Grimlock, Optimus (Rare), Chromia and Nemesis Prime. And I'm only 7 rare Battle Cards away from having a complete set of 3 of each battle cards...but damn. Have a ton of extra crap to sell/trade off though, so there's that.