Dragon Broodmother Dragon Broodmother offers a path to a wide board of big Dragons thanks to its token generating ability
Reiki, the History of Kamigawa draws you cards, Garruk, Caller of Beasts helps you find creatures, Captain Sisay tutors for legends, Chief Jim Hopper creates Clue tokens to help you draw cards, and Old Gnawbone gives you Treasure tokens
There're other characters like Zagorka, Sash and Waistcoat, and the three Numena I'd like to see as well, but given this is focusing on returning characters, those ones are probably for another article
First off, this has less downsides than your average Howling Mine since you get the first crack at the additional card
By linearity of expectation , the average equals the sum of each guild's chance of appearing at least once among the ten revealed cards: with 6 cards a guild has a 48.1% chance to show up, and 10 48.1% = 4.81