While the "ease of flipping" category is, in large part, a product of the number of defense counters on the battle (battles range from three to seven defense counters, and a battle with three defense counters will be much easier to flip than one with seven), it also takes other factors into consideration, like whether the battle makes creatures (if so, we can use them to help defeat the battle, making it easier to flip) or whether the battle acts as removal (which can get a blocker out of the way, making it easier to attack and defeat the battle)

Deck Filters Doom's Time Platform 25%inclusion 24%synergy 2 decks 8 decks Doc Samson, Super Psychiatrist 13%inclusion 11%synergy 1 decks 8 decks Doctor Jane Foster 13%inclusion 12%synergy 1 decks 8 decks Donald Blake, Guise of Thor 13%inclusion 12%synergy 1 decks 8 decks Night Nurse, Healer of Heroes 13%inclusion 12%synergy 1 decks 8 decks High Synergy Cards The Tenth Doctor 93%inclusion 90%synergy 41 decks 44 decks The Eleventh Doctor 91%inclusion 87%synergy 40 decks 44 decks Trenzalore Clocktower 89%inclusion 86%synergy 39 decks 44 decks The War Doctor 86%inclusion 83%synergy 38 decks 44 decks The Thirteenth Doctor 86%inclusion 83%synergy 38 decks 44 decks Regenerations Restored 82%inclusion 80%synergy 36 decks 44 decks The Ninth Doctor 82%inclusion 79%synergy 36 decks 44 decks The First Doctor 77%inclusion 74%synergy 34 decks 44 decks The Sixth Doctor 75%inclusion 71%synergy 33 decks 44 decks Gallifrey Stands 73%inclusion 69%synergy 32 decks 44 decks Top Cards The Eighth Doctor 73%inclusion 69%synergy 32 decks 44 decks The Fifth Doctor 73%inclusion 69%synergy 32 decks 44 decks The Second Doctor 73%inclusion 62%synergy 32 decks 44 decks The Fourth Doctor 73%inclusion 69%synergy 32 decks 44 decks Everybody Lives

How do you go about picking those cards
Your chances of opening any one of them from just nine packs isn't exactly great, but hope is a powerful thing