So instead of using your turn to attack your opponent directly, rather use it to get rid of their vigilance creatures
An instant is more powerful than a sorcery, but the requirement to attack to net a card is much easier to accomplish than having five different mana values in your graveyard
This usually helps speed up the process of powering up Moves that have more than one Colorless Energy requirement
So at worst you have a 6/6 samurai, but at best you hit a living weapon, job select card, For Mirrodin!, Meteor Sword, Embercleave, and the nasty Nazgl Battle-Mace
Any artwork that features these two Pokemon is bound to stay in demand, so expect this card's value to increase with age
Its effectively a 4/4 Eternal Witness, and it doesnt take much effort to give it an additional relevant keyword like flying or trample