The added benefit of vigilance means anything that survives your armys wrath will have to crack back into a big, bad 5/5 giant
And it works on any form of leaving the battlefield, so you can bounce or exile or even shuffle it into your library, so it works with effects as diverse as Terminus, Fleetfoot Panther, and effects like Goblin Bombardment and Crystal Shard
Who doesnt love a good Taurean Mauler or Changeling Outcast in their deck
It's wonderful for slowing aggressive plays and gives you a massive mana advantage when targeting big creatures
Include Dragons with death triggers or recursion, so sacrifices generate value beyond the initial damage
The same applies if youre the Tokens player, and you want to obliterate the more expensive creatures