Instead of banning Vein Ripper, the card that caused the rise of Rakdos Vampires, Wizards of the Coast decided to ban Sorin, Imperious Bloodlord, because the cards existence makes any massive top-end Vampire printed in the future a threat to the Pioneer format
As a spirit lord, this card provides power, toughness, and hexproof to all of your spirit creatures
SufferFromEDHD on Sun Quan, Disgraced Lord of Pestilence 3 years ago Cut 3 islands for Inkmoth Nexus, Vesuva and Deserted Temple
Krark-Clan Ironworks can also provide infinite mana with Myr Retriever Scrap Trawler, or Junk Diver, as well as any card that makes artifacts cheaper
The attack effect is cool, but I'm not sure what value you would stand to get from it aside from a Boros Charm , Double Cleave , Waves of Aggression , Seize the Day or maybe a Austere Command
The best part about this card is that the benefit stays with you after the creature dies in the form of an enchantment, which is usually harder to remove