Cost of Lost Memories

The odd one out of the three mutually-exclusive endings - it needs Lily's bar under 100% while you take Adam's hand, the exact opposite of Making New Memories. Since your thorough main run will have the bar full, save this for your Repeating Protocols NG+ run: skip the memory-stick/document collecting, keep the bar low, take the hand. Two birds, one run - you wrap up NG+ at the same time.