Well, whether we agree with it or not, Faithless Looting is no longer part of the Modern format
Also, I should note that the card's ability only works if you legally got it into your hand
It's a small value engine, but it is definitely not among the most powerful artifacts in the game like Black Lotus, the five Moxes or Time Vault
The ultimate is quite easy to pull off with Sorin growing so effectively and protecting himself well and gives black a lot of ways to deal with things it otherwise struggles with by using your opponents cards to get the job done for you perhaps with a Disenchant they handily had for you
D&D and Magic go together like peanut butter and chocolate
Taking an extra turn as soon as she's cast means she has pseudo-haste, and annihilator 6 can typically decimate most of your opponent's board (quite flavorful if you think about it)