I haven't spent any real money in Arena, and have only improved my deck via spending in-game earnings. My favourite deck right now is:
It's time for the Sporeweb Weaver to go, and I'm wavering on the Lovestruck Beast. Most of the rest I really like, but I'm wondering if there's a good deathtouch creature that can be inserted that can help instakill with Rabid Bite and Ram Through. Thoughts? My last upgrade was completing the Elder Gargaroth playset and upping Nylea, Keen-Eyed at the expense of an Arasta of the Endless Web, which has been a good change.