RNG system, bullet sponge bosses. Large explorable area's (not by much in destiny but still), a main hub city for getting bounties/missions, a cast of characters with their own unique skills that change up gameplay, enemies health and level above their heads. See the thing is I love both games and all of these examples are super generic RPG elements so yes borderlands and destiny are very similar but who cares?? They're both pretty fun games.