1. reach level 20
2. you need to use a deck that doesnt have over 25 in the sum of your deck's levels. for example, you can use 3 lvl 5 cards, and 5 lvl 2 cards, thats 8 cards and a sum of 25, its playable. any higher than 25 and its not qualified as a ELO deck.
3. also, your deck must not contain the following cards, DJ Korr, General, or Kiki.