Hey early risers! Enjoy a +2 to each of your SPECIAL attributes from 6 am to 12 pm, but suffer -1 from 6 pm to 6 am when you're not at your best.”— Fallout: New Vegas description
From 6AM to 12PM, you gain +2 to all SPECIAL stats but from 6PM to 6AM, you suffer -1 to all SPECIAL stats. It is somewhat mitigated by the Night Person perk (resulting in a +1 INT and PER at night), and synergizes extremely well with Solar Powered (+2 Strength while in sunlight).
Combined with Claustrophobia, being outside from 6AM to 12PM increase each SPECIAL stat by +3, while being inside from 6PM to 6AM reduces each SPECIAL stat by -2.
Behind the scenesEdit