Fantastic, deck building community, tactic game with singleplayer campaign. 
Beginners hints:
Battles are fought in turns, on small maps and with only 3 heroes. Attacks are boosted by cards randomly drawn from a prepared deck. In PVP fights, defender prepares a deck for AI to control.
1. Ranged team. Archer, mage and priest. Slow and immobilize enemies.
2. Join a team as soon ad you can. Look for best team available. On level 10, check top teams for vacant place and apply. Team rewords are a great boost.
3. Do not dismantle ability cards. Selecting them is a loss of time that could be used for farming. There will be automatic select of overstock cards.
4. Dismantle all unused equipment. Keep only weapons with elemental damage and cripple/poison/daze effect. They are usable on events.
5. Buy legendary (4 stars) battlefield - it produces Cold Steel Ingot.
6. The 5 stars battlefield also produces Cold Steel Ingot and not Imperial Tokens.
7. Push story progress untill you beat Beatassilica at Chapter 2. It unlocks new daily quests to upgrade your Mythic Equipment and Abilities.