MTG Dragons: Values

•16-19: On each player's next turn, all creatures they control gain, "At your upkeep, roll a d20. if the result if 11-19, put a +1/+! counter on this creature. If the result is 2-10, put a -1/-1 counter on this creature. If the result is 1, exile this creature. If the result is
20, this creature gains flying, indestructible, trample and +7/+7.