, ▁the ▁situation ▁shift ed ▁after ▁C ao ▁C ao ▁received ▁advice ▁from ▁his ▁strateg ist ▁J ia ▁X u , ▁who ▁concluded ▁that ▁changing ▁the ▁general ▁rules ▁of ▁succession ▁( prim ogen iture ) ▁would ▁be ▁dis rupt ive ▁– ▁using ▁Y uan ▁Sh ao ▁and ▁Li u ▁B iao ▁as ▁negative ▁examples . ▁C ao ▁Pi ▁was ▁also ▁fost ering ▁his ▁image ▁among ▁the ▁people ▁and ▁created ▁the ▁sense ▁that ▁C ao ▁Z hi ▁was ▁waste ful ▁and ▁lack ing ▁actual ▁talent ▁in ▁govern ance . ▁In ▁ 2 1 7 , ▁C ao ▁C ao , ▁who ▁had ▁received ▁the ▁title ▁of ▁a ▁v ass al ▁king ▁– ▁King ▁of ▁Wei ▁( <0xE9> <0xAD> <0x8F> 王 ) ▁– ▁from ▁Emperor ▁X ian ▁( wh om ▁he ▁still ▁paid ▁nom inal ▁alleg iance ▁to ), ▁finally ▁declared ▁C ao ▁Pi ▁as ▁his ▁he ir ▁apparent ▁( 世 子 ). ▁C ao ▁Pi ▁would ▁remain ▁as ▁such ▁until ▁his ▁father ' s ▁death ▁in ▁ 2 2 0 . ▁ ▁As ▁King ▁of ▁Wei ▁C ao ▁C ao ▁died ▁in ▁the ▁spring ▁of ▁ 2 2 0 ▁in ▁Lu oy ang . ▁Even ▁though ▁C ao ▁Pi ▁had ▁been ▁his ▁father ' s ▁he ir ▁apparent ▁for ▁several ▁years , ▁there ▁was ▁initially ▁some ▁confusion ▁as ▁to ▁what ▁would ▁happen ▁next . ▁The ▁app reh ension ▁was ▁particularly ▁height ened ▁when , ▁after ▁C ao ▁C ao ' s ▁death , ▁the ▁Q ing z hou ▁Corps ▁under ▁the ▁general ▁Z ang