A tool string disposable in a wellbore includes a plug configured to seal against an inner surface of a tubular string disposed in the wellbore, and a setting tool coupled to the plug that includes a piston slidably disposed in a setting tool housing of the setting tool and including a central passage, and a combustible assembly disposed in the passage of the piston, wherein the combustible assembly includes a housing and combustible material disposed in the combustible assembly housing, wherein, in response to a pressurization of the central passage of the piston of the setting tool, the setting tool is configured to actuate the plug to seal against the inner surface of the tubular string.