Attack ground

I'm making an ability called flaming arrows and I'm using the spell plague (meatwagon) The problem is that for a plague (meatwagon) to work the unit that has the spell must have an artillery weapon type. The problem with this is that an artillery attack type gives the unit the attack ground ability which i don't want. So if theres a way to make the spell work without artillery weapon type or a way to make artillery weapon type not have attack ground, PLEASE TELL ME!

Not sure but does that come with seige damage type? Ive been asking myself how to add or get rid of that for a while...

ok. i figured out you cant remove attack ground, so i need a way around the ability needing artillery weapon type.