To defeat lvl 16 and lvl 17, you have to be able to produce your titan unit.
1st) You need to have at least 10-20 magicians
2nd) Flood halfing to slow him down as much as possible
3rd) Use your special power as often as possible.
For Defeating Lord of Hell. Do not spam units. He will slam the floor when you exceed a certain amount of units. Every time he slam the floor your castle will take 500 dmg. Next, he absorbs range and magic dmg. So no use using archers and magicians. Best way is to send angel knight, titan and red dragon. but of coz the number should not exceed 8 (have not tried increasing to 9 though, but 8 is enuf to hold the army of darkness)
recommended army: 1-2 Angel knights, 2-3 titans, 1-2 dragons.
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