There are two versions of Krenko. Mob Boss shown here is best for goblin tribal, but they recently printed Krenko, Tin Street Kingpin, too. If you like +1/+1 counters, he's a good addition to a deck. Not quite as good as a commander though, in my humble opinion. I have a red/green deck of stompiness where he fits in as support though, because it adds extra counters to him sometimes as a bonus.