Majmu al-Fatawa al-Kubra is a valuable but secondary collection of Ibn Taymiyyah’s rulings. If you find a free PDF, use it only as a supplement to the main Majmu’ al-Fatawa (Ibn Qasim). Be extremely cautious with unverified PDF scans—textual errors can lead to serious misunderstandings of Ibn Taymiyyah’s positions. For authoritative study, invest in a printed, verified edition (e.g., Dar al-Wafa or Dar Ibn al-Jawzi prints) or use the Shamela digital text.