On Landulf's death, he reasserted his claim with the support of a large faction, though he was opposed by Lando III. He took the cities of Teano and Caserta, while Lando's faction held Caiazzo and Calino. Landenulf had the support of Guaifer of Salerno, so Pandenulf tried to get Gaideris of Benevento and the strategos Gregory, then together in Benevento.
Following Landulf's death, he regained his claim with a large following, but was opposed by Lando III. He conquered Teano and Caserta, while Lando's forces held Caiazzo and Calino. Landenulf had the support of Guaifer of Salerno, so Pandenulf sought allies in Gaideris of Benevento and strategos Gregory to join him in Benevento.