Sam Ross designed Rosina's cocktail program at The Palazzo — the same Attaboy NYC creator whose Vegas Strip lineage now runs three rooms (Rosina + Electra Cocktail Club + Golden Gai Cocktail Club via protégé Luis Lopez). The 1,100-square-foot 65-seat lounge sits on the Palazzo casino floor with a Champagne-and-Penicillin signature program. Thursday-Sunday late-night format (7 PM to 2 AM) keeps the energy controlled rather than club-tier. The room is cocktail-bar register at its most serious — bar-tier LP-tier where Ross's Attaboy discipline carries through. For the most-credentialed cocktail program inside The Palazzo.