Ok, so I am familiar with the idea that if you enjoy something really much, you should give back so here is me trying to give something back.
This is meant to be a complete guide regarding a wide range of things you are supposed to do in Eternal Arena.
First of all, Hibernus ->> get Hibernus A.S.A.P it is one of the strongest heroes here, gear him with crit chance/ crit damage for monster hunt, bloody battle, duel and sneak in some life steal for activities like Trials that require you to have some sustain
STORY: there are different combinations for different parts of the story chapters, you can usually find youtube guides for the most difficult ones. Always raid THE LAST BOSS FIGHT you did, I am not 100% sure but it has an increased chance of giving you items/gold and also includes a chance for Awakening Gems.
1.Tavern: one of my favorite places, tavern is very important because here is the place you are going to spend a lot of time and Diamonds, testing your luck in Draw 10. The free draw each day offers you usually a 1 Star hero that most likely is going to be converted into Soul Essence. Once every 4-5 draws a 2* hero is going to be awarded.
2.Blacksmith: good place to get gear but only from the Free Draw, never and I repeat, NEVER do "Draw 10", it is nothing you can't get by other means. Same as Tavern, Blacksmith free draws are going to usually give you green pieces of gear and every 6-7 draws you will get a Rare Blue piece.
3.Goblin Hunt: doable twice a day, good place to maximize stamina gain; I recommend you to use Sylvia ( if she is at least 3 star) because it is fairly easy to get, and the Frost rune; it will usually boost the stamina gain by quite a bit since the AoE of Sylvia's ultimate fits really well.
4.Monster Hunt: already a decent guide for Monster Hunts, I recommend you to check Five's Monster Hunt Guide on forum; As an advice, you usually want to go for Critical Strike items for this one and, in special cases, for Attack Speed/ Basic Attack Bonus;
5.Bounty: Never do the gold tasks, even if they are 3 stars, they are fairly useless. My suggestion for you is to do them in this priority: Gems(every 5-6 days, a bounty task will have gems as a reward) > Blue(rare) items > Runes> Green Items > Soul Essence > Grey items (common) > Gold. Spending Bounty Gems should be done to get Accessories at first, then use them for whatever you please.
6.Invocation: Do invocation as often as possible for your main hero (usually you want to bring Hibernus as high as possible in terms of stars or mastery)
7.Rune Wars: for rune wars, my advice is to first take as many new runes as possible, and after you got a decent amount, do Rune Wars only for runes that you already own; they are going to be converted into 5 rune shards. First runes you want to bring to a decent level are the ones that give basic stats like Might;
8.Trials: for Trials you want to have as many AoE heroes as you can, If you are new Hibernus and Sylvia are great, especially Silvia since she can heal your other heroes. With Hibernus try to group all the monsters and use your Fatal Flurry on as many as possible. Here aswell you want to have more Life Steal or Spell Vamp oriented builds.
9.Challenge: you should only challenge the same hero per day, because you will get a guaranteed blue item;
10.Bloody Battle: do this as often and use the Bloody gems to get those sweet rewards;Good Bloody battle heroes: Hibernus, Bane, Agony, Cerberus, Thanatos, Oya, Rurik, Xah'bbah, Raijin, Rasha, Cedelyon,Ingvar;
11.Tournament: challenge teams and collect rewards every day.
DUEL: prioritize getting as many duel gems every day to acquire boots for every hero you actively use. Good duel teams:
-For beginners: Hibernus, Wukong, Sylvia (keep Sylvia in the back so she can finish casting her ultimate) etc;
-Intermediate: Hibernus, Cerberus, Charon; Hibernus, Rhagavar, Sylvia; Hibernus, Bane, Rhagavar; Hibernus, Raijin, Tai; Viscern, Sylvia, Rhagavar; etc;
-Advanced: Omaeus, Rurik, Oya; Omaeus, Rhagavar, Hibernus; Omaeus, Kagemasa, Cedelyon; etc;
Runes for duel: usually you want to get Summit rune from duel exchange to reduce the duration of crowd control, and always have Sanctum rune, it's one of the best;
GUILD: do Manors, Rescue, Elder Dragon, Bosses everyday to maximize Guild Contribution income so you can get 7th Rune slot and then get more Rare pieces of gear.
ARENA: do arenas as often as possible, if the difference in power is greater than 5-6 k you can leave your team on auto, to increase the amount of gold and exp you get. Yeah it seems boring, but trust me, it helps your progress by a lot.
Game menu (the little + on the right bottom corner of your home screen):
Inherit: transfer exp/mastery/stars from a hero to another;
Transmute: same as inherit, just that you do it with gear;
Forge: forge 5 items of the same type into one of advanced type; here I noticed that you have some kind of bad luck system; you will never fail more than 3-4 times in a row, so if you craft epic gears into mythics, be sure you first try to craft green gear until you fail about 3 times in a row.
Craft: the recipes usually tell you what you need to craft different things;
Jewels: unlocked after level 60, jewels can be socketed into gear, boosting your stats by a bit;
Artifact: unlocked after first getting some Minas Amber ( the very first moment you join a guild, do boss challenges and go to boss shop and get Minas Ambers)
Personal advice for the game:
HAVE PATIENCE, I know it is hard and tempting but have patience and don't spend your diamonds on nothing and I mean NOTHING until you encounter an event. Prioritize Rurik, or Oya events, hence they are 2 of the best, if not the best heroes in the game at the moment;
THINK FOR YOURSELF, use your brain to figure out what is best for every hero, what build you should use for any encounter;
Every week, without paying anything, you can gather 756 Diamonds from daily sign in+7* 70=490 Diamonds from Elder Dragon +7 * 35=245 Diamonds from Tasks + 7*30=210 Diamonds from Arena(Twilight forest will give you a Diamond reward every 4-5 matches, so basically it's daily) + 100 Diamonds from Monthly Sign In(at first it isn't 100, but it gets higher the more you go on so I rounded it up to 100) = 1801 Diamonds per week; If you add Monthly Card and Premium card ( which I recommend you to get, they are very very good to have) +200*7=1400 Diamonds so in the end you can gather around 3200 Diamonds every week, so in 4 weeks you can have about 12800 Diamonds which almost guarantee that you get something good from the incoming event, whether it is Gear up Or I want you or Hero event;
Also keep in mind that power isn't everything, the stats are really important; A 4- star Rare item is better than a 1-star Epic item;
If you have any question, feel free to ask at any time