The squad includes representatives from seven nations for the games, which will have international status, in Lahore on Sept 12, 13 and 15.
Hashim Amla, Morne Morkel, David Miller and Imran Tahir are the other South Africans.
Three Australians -- George Bailey, Ben Cutting and Tim Paine -- have been selected alongside two West Indians and one player each from England, Bangladesh, New Zealand and Sri Lanka.
Former Zimbabwe captain Andy Flower will coach the squad.
Pakistan have played most of their home games in the United Arab Emirates over the past eight years because of security concerns.
Barring a short visit by Zimbabwe two years ago, Pakistan has been starved of international cricket since 2009, when gunmen attacked a bus carrying Sri Lankan players in Lahore, wounding six players and killing six security staff and two civilians.
Punjab's local government has promised watertight security for the World XI series.
World XI squad: Faf du Plessis (capt, SA), Hashim Amla (SA), Samuel Badree (WI), George Bailey (Aus), Paul Collingwood (E), Ben Cutting (Aus), Grant Elliott (NZ), Tamim Iqbal (Ban), David Miller (SA), Morne Morkel (SA), Tim Paine (Aus), Thisara Perera (SL), Imran Tahir (SA), Darren Sammy (WI).
(Reporting by Neil Robinson; Editing by David Goodman)
