new troop! THE WISPS! Trust me, I thought this out

Whisp
20, 25, 30, 40, 50 DE
2 minutes
1 housing space
50, 57, 65, 75, 90 DPS
50, 75, 125, 200, 300 hit points
26 movement speed

25k, 40k, 65k, 85k to upgrade (in dark elixer)
3, 7, 10, 15 days to upgrade
Lab level 6, 7, 8, and 8 again to upgrade

Description: "Everyone knows about these fiery whisps forged from the fires below, and how much trouble they get in if they provoke one. When killed they make a tiny explosion…and because of their flaming body inferno towers can not target them.

Run through: inferno towers will not target. Fighting fire with fire doesn't ever work…they are ground troops but stay slightly afloat off the ground. Low health and Attack power…they explode in a 2 by 2 radius (like balloons when they die) when they do explode they do the exact same amount of damage. They are unlocked at DE barracks 7. They are the colors of fire…but change different colors when they start relieving damage. When at half health their damage increases by 10. When they explode they do 10% damage to any OTHER troop around them. Whisps hitting another whisp does not do anything though

Questions i have:

should they be able to target inferno towers?
should mortars be able to hit them since they are floating off the ground about a foot?