The nightfall is an easy solo on warlock and Titan. Use tlaloc, sun, angel of light. Use no time to explain (for boss and tank, blessing, and empyrean bellicose for Titan. Any special works. I used a void fusion for warlock to strip captain shields then melt with tlaloc, and a snipe on Titan. Got through with 7 minutes left. Use a rocket for the multi shielded captains but make sure you're in the air when it explodes.