@mantez As has been mentioned, jose.abalos (an avalanche employee) has posted a full list on the first page of this topic, stating Nova is compatible with the Avengers playset. The Official site doesn't state Nova won't be an Avengers crossover character, it is constantly being updated and as yet just does not include the icon indicating this. Also this Family Gamer TV video from E3 mentions Nova as a crossover in Avengers as well at the 12.00 mark: