collect spell and wormhole spell
I have two ideas:
1.collect spell(need a better name): collect still-alive troops in the area and you can even use them again(remaining health of each type averaged),or you can save them for the next battle. upgrade to enlarge the area or upgrade to reduce the cost.
2. wormhole spell(also need a better name...): place this spell and you can put troops down here...... even on buildings and walls. upgrade to put more troops(housing space). Like lvl1 you can put 40 housing space of troops, lvl2 45.....
