Ice bolt

You hurl a mote of Ice at a creature or an object within range. Make a ranged spell attack against the target. On a hit, the target takes 1d10 Cold damage

if aimed at a specific limb the creatures to hit is raised by +2,if the specific limb of a medium sized creature is hit with this spell 3 times in a consecutive row the target takes a dc 15 constitution saving throw and on a fail each turn that limb is frozen over and cannot be used in anyway.on each of that targets turns they can use their bonus action to make another saving throw for use of their limb again.for each creature larger then medium the amount of times needed to be hit before freezing is increased by one.for creatures under medium size the ac of the target is increased by +1 for each size under medium,and the amount of hits needed decreases by 1

Cantrip Upgrade. The damage increases by 1d10 when you reach levels 5 (2d10), 11 (3d10), and 17 (4d10).