A detailed three-dimensional Monte Carlo nuclear analysis is presented for the heavy-ion-beam-driven reactor HIBALL. Neutron target interactions leading to neutron multiplication, spectrum softening, and gamma production are included in the model A 0.66-m-thick blanket cooled by Pb83Li17 reduces the radiation damage in the HT-9 ferritic steel first wall to 2.7 dpa/full power year, allowing it to last the whole life of the plant. The overall tritium breeding ratio and the overall energy multiplication are 1.25 and 1.27, respectively. The four reactor cavities in the HIBALL power plant yield a total thermal power of 10 200 MW(thermal).