Draggy Towers

You can move anything, even if it doesn't create a match.
You can drag anything off the edge into the water.
You can drag stone into the castle to heal it 1 heart. The castle has a maximum of 15 hearts.
You can drag an arrow tower into the castle turret to arm it with arrows. The arrow tower stays there forever.
Castle windows show you what resource is going to fall in next in the column.
Castle gates let you use an extra space in the castle to make matches. If a dragon hits the gate, it deals double damage.
Icebergs slow dragons on them, just like a silver Ice Wall.
A tower on a hill will shoot farther. Ice Wall on a hill will slow longer.