After months of theory crafting various kinds of GB decks, this is the one I keep coming back to. Running as pure as possible with both the armored XYZ package and the Underworld Package just to help clear annoying boards. This deck has seen consistent success in building boards and has been plenty of fun to work on. Later on I'll do combo lines and all of that jazz but it's pretty straight to the point.
This deck wants to go second, with the amount of non engine you can carry having a good mix of hand traps and board breakers has helped consistently. Troika Griar is in the ED specifically to help go over towers if necessary, and can help in the grind game as if you can't swing for game in T2, you can usually out stall them using negates and various interruptions (Armored package ear, goblins crazy beast + Gabonga, and even the negates like Larz + Gossip Shadow.
That being said if you side into going first and don't have a way to get Gen or Ken to opponents field the best end board is usually a Gabonga, I:p, and either a Larz or Gossip shadow or if you can swing it Totem Bird + Gossip Shadow.