Related Clues:

• Christopher Cross "Arthur's Theme (Best That You ___)"
• Van Halen "Don't Tell Me (What Love ___)"
• Demonstrating determination
• 'Don't doubt me!'
• ''I've got this!''
• This puzzle's theme and a great attitude to have
• Alternative to bottle party? It's possible
• Braggart's retort
• Positive toilet's the same as before
• "I'll handle it!"
• Playground retort to a doubter
• Boaster's assurance
• Very confident
• Ready to get stuck in lavatory? Repeat that
• 'On it'