Head On, which likewise conveys the fragility of human life, is the installation that earned Cai the greatest accolades: It shows 99 wolves baring their teeth, charging in an arc toward a glass wall and then smashing against it. Despite painfully flipping over after hitting the wall, they throw themselves at it one after another to demonstrate the will of the pack.
同樣呈現人性脆弱面的《撞牆》，則是蔡國強最令人讚嘆的裝置藝術作品：99 匹大狼呲牙裂目、沿著弧線猛力奔騰，向前方高聳的玻璃牆撞去；即使撞上後痛苦地翻跌，卻又為了貫徹群體的意志而一再重返撞牆。