Megavore, opens some interesting choices for a team of monsters, but then you would have some complications with mana generation in this aspect. But you could use Megavore + Scylla or Megavore + Kraken to focus on damage for the last enemies.
Glaycion as the first troop could also work for a monster themed team as a tanker and a gem converter for Blue+Doomskulls and paired with Scylla’s Bonestorm you can probably finish some battles very quickly.
Ignoring the monster theme is also ok, and you could probably try something using the Trolls, combine two trolls together that can double the gems of each other colors and Megavore so you can trigger his killing trait multiple times and cast his spell.
You can also try something like with with the classic duo of Valkyrie + Alchemist and maybe you could throw a good troop that also have a trait trigger for 4/5 matches. Maybe Khorvash or Mab, you could also use Mercy to have some cleanse, healing and extra loops.