Board Thread:Card Unit Builds/@comment-25271211-20140821040907/@comment-25133996-20140821071134

So you may need more stronger cards in your collection... Fight more F/AWs may help you in getting more SR cards, it may take some luck. (or try some random luck with free premium/ultimate summoning tickets, they are available in campaigns)

Will try to take: (absolutely maxed skill level and status) HSR Dragon Princess HR Millionare R Ghost

... for the last two slots i don't have any idea... But you CAN CONSIDER : SR Circe or any critters that have a opposite elements to the campaign F/AW or High Vampire, but not so recommended

To get stronger cards, the only way (not fast but absolute) is to fight more F/AWs. But that will challenge your endurance. :D