Of course, the one powerful tribe not already listed here was the one that stood to benefit the most, the Merfolk, who are still a very powerful tribe in the Modern and Legacy formats today, if not even more powerful with newer cards such as Master of the Pearl Trident and Master of Waves at their disposal. Several top decks did instead sideboard about three copies of this card and made good use of it to shut down tribal effects (and deal with pesky Mutavaults) and make their creatures often just weak enough with their Lord bonuses negated to be dealt with in simple chump blocking fashion.
Will we ever see it in a competitive sideboard again? Tribal decks aren’t quite what they were, but you never know. Goblins are still a thing, as well as Merfolk. Humans could rise again in Modern with so many new variants of the Soul Sisters deck cropping up. If you’re running blue and your meta-game is ripe for the picking with tribal decks, it may not be a bad play to sneak a few copies of these in. They most likely won’t see it coming!