Arena gets in on the GameAwards fun-type those two words on their store page, then click Redeem A Code to get the ESports starter kit, of which I have no clue, but hey its free.
Edit; Apparently you get the following 25 cards:
You get 25 cards to use in your decks: 1x Cleansing Nova 1x Ghalta, Primal Hunger 1x Risk Factor 1x Search for Azcanta 1x Vraska’s Contempt 4x Conclave Tribunal 4x The Eldest Reborn 4x Lava Coil 4x Merfolk Branchwalker 4x Sinister Sabotage