Makeshift Fortification

At the beginning of your endstep, put a security counter on Makeshift Fortification. If you
attacked this turn, instead remove a
security counter. Then, bolster X, where X is
equal to the number of security counters on Makeshift Fortification. (To bolster, choose a
creature you control with the least toughness or tied
for the least toughness among creatures you control.
Put X +1/+1 counters on that creature.)