“Although I am staying here, you may stay anywhere throughout Muzdalifah.” [Muslim]
Muzdalifah is also being referred when Allah mentions in Surah Baqarah in Quran,
“When you leave Arafat, then remember Allah at the Mash’arul Haram.”
It is wajib for a pilgrim to pray Maghrib and I’sha prayer together at I’sha time. Pebbles are also usually collected from Muzdalifah for stoning of devil at Jamarat, although one can collect them from anywhere.