A half-dozen horses have been added to the second list of invitees for the GI Pegasus World Cup Invitational S. to be held Jan. 29 at Gulfstream Park. Those joining the original list, headed by likely Horse of the Year Knicks Go (Paynter) and GI Breeders' Cup Dirt Mile hero and 'TDN Rising Star' Life Is Good (Into Mischief) are recent Tenacious S. winner Chess Chief (Into Mischief); Fearless (Ghostzapper), last-out winner of the GIII Harlan's Holiday S.; Law Professor (Constitution), who took the off-turf GII Santa Anita Mathis Mile...