Just A Bone as depicted in the image.
Just A Bone is common card in Tower of Doom. It’s a buff spell, but it is common just like King's Crown or Farm Tractor. It has a low cost because of its buff on only one class, while still debuffing only one class. This specifically buffs and gives +1 to Pet Blooks (🐾), While taking -1 from Forest Blooks (🌲). It is not usually seen with Magic Seedling due to its debuff on this type.