A: At the top of the page above the rewards there should be a green and blue tab that says manage your pledge. If you click on that you should be able to adjust it there. Click on the new reward you'd like and then at the top add in the price amount from the old reward or any additional ones you like to the pledge total. At the end of the kickstarter we'll be sending out a survey at which time you can list which covers you'd like as well as to let us know what additional rewards you have pledged for.
A: Yes, you can get them both by selecting one and then adding the amount from the second reward of your choice to your total pledge. As for the Extinction Edition sketch covers you can also get those as well (FREE while supplies last for Diamond tier) if your pledge reaches the Diamond tier level or get them separately by selecting their individual reward.
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