Tateworlds: Toyshop

/testfor @p[r=10] {Inventory:[{tag:{SkullOwner:{Id:"6d46f5a1-a833-414c-ba0d-9842cb59316e"}}}]}

yellow
/testfor @p[r=10] {Inventory:[{tag:{SkullOwner:{Id:"60E034AE1-AC24-7980-805E-FE275D1AC9DD"}}}]}

Green
/testfor @p[r=10] {Inventory:[{tag:{SkullOwner:{Id:"990d87d1-27ad-4b30-80c4-689394362ca9"}}}]}

Red
/testfor @p[r=10] {Inventory:[{tag:{SkullOwner:{Id:"cc5fdd1a-60f8-40d6-b667-a197e39f3bae"}}}]}