The first time I played epic war 4 i was amazed on the difficulty so I used different units

Current ones:
Heros:
Simon the magician Lvl 5
Cassandra the Queen Lvl 5
Kara the Slayer Lvl 5

Units:
Goblin Lvl 5 Pop: 35
Valkyrie Lvl 5 Pop: 12
Elf Sniper Lvl 5 Pop: 15

Titans:
Celestial Angel Lvl 5:
Health 15000
Attack 850
Sky Dragon Lvl 5:
Health 19500
Attack 550
Lord of Fire Lvl 5:
Health 16666
Attack 666

Which Titans should I use:

Well Titans are the most powerful monsters of the game and are the best for the bonus challenges.

The first one I chose was the celestial angel
My second was Sky dragon
Last was lord of fire

Celestial Angel:
A great multi attacker and can be very helpful distracting monsters like the Black Lord of fire in the final challenge on hard

Sky Dragon:
This monster can be helpful and has the most health a titan can have so I would also have this to help. The best Bonus Challenge its on is the goblin madness

Lord of Fire:
Best Titan next to the Sky dragon and the Angel.
It can help in all bonus challenges because it kills the castle first before any other titan does

Great Diablos:
Worst titan.
Dont bother going for this titan because its bassicly a big meat shield and it takes forever to attack
>.>