I would personally sideboard the Soul Snuffers as their utility is limited to token/weenie decks. Ball Lightning isn't too terribly expensive, and can be hit with tainted strike to land a healthy infect blow on the cheap. Phyresis is a more permanent option for giving infect. Also, the new Titan's Strength is a pretty solid boost, though I'm unsure how expensive it is at this time. (It's common, so it shouldn't be too bad.)

Thanks for your input! I agree with you that Soul Snuffers loses it's value when not fighting token/weenie decks, and that the side board may be a good call.

As for your replacement suggestions, here are my thoughts:

• Ball Lightning : In competitive modern, if you don't win by turn 5-6, you've already lost. As this deck is based around one hitting your opponent, and nothing in my deck is natural infect/wither, hitting for 6 damage/poison seems negligible.

• Phyresis : My issue with a more permanent infect is that in my experience Nova Chaser gets summoned then either dies, or you hit that turn and win. Nova Chaser very rarely stays on the battlefield longer than 1-2 turns. If I were to go this route, I believe Glistening Oil may synergize better with how this deck works.

• Titan's Strength : This may be a good call, although it would be nice to replace Soul Snuffers with another creature. Also, I have yet to have a game where Nova Chaser has failed to deliver a killing blow (knock on wood), so I don't know how much value +3/+1 would be. I will continue testing and keep this card in mind if Nova Chaser begins to fall short.

I would love to hear your thoughts, thanks again for your insight!