Simplify the following text for a Grade 10 native English-speaking person.
Original: Pizarro staged a mock trial and found Atahualpa guilty of revolting against the Spanish , practicing idolatry and murdering HuÃ scar , his brother .
Simplified: Pizarro staged a mock trial and found Atahuallpa guilty of revolting against the Spanish and murdering HuÃ scar , his own brother .