The only difference between Bracket 4 and cEDH is that you arent tuning your decks for an expected metagame
Collector Booster packs are filled with cards in special treatments at various rarity levels and inside each Special Edition Collector Booster are 15 cards, comprised of 5 Rare (or higher, such as Mythic Rare) cards, 5 Uncommon, 4 Common cards and 1 Land card
The random nature of what you can find (or if you hit anything at all) makes this card much more fun in a casual setting, especially for your opponents
This white-blue deck is a very classic example of a control deck, featuring many of the most recognizable features of the archetype a word we use for a recurring strategy with numerous possible variations
Breed Lethality seems to be the runaway hit of the five precon decks, and everyone is brewing up decks featuring Atraxa, Praetors Voice
Hive Mind + Summoners Pact Combo Theres an interesting interaction between Hive Mind and Summoner's Pact (or any of the other 0-cost cards in that cycle)