Hi there. Mint Retrograde is randomly available as the bonus focus reward from Pinnacle activities in the portal. Completing the activity guarantees that reward from the chest. You'll need to check each day for when one of them offers it as a focus. Mint Retrograde can also drop randomly throughout Pinnacle activities. T5 is guaranteed if you do Pinnacles on Grandmaster and get an A-A+ or you do Ultimate difficulty. Below that they are random drops. Verify the activity forecast to confirm what your projected grade will reward.