*Not all information is correct and much of it is my personal opinion*
*PvP info is now out-of-date, I'll make corrections when things settles down*
0) If a hero requires more than 20 tokens to unlock, only unlock them via the portal--do not click that ever-so-tempting "Summon" button.
1) As a rule, you are awarded player XP quicker than the gold and xp potions required to keep your roster leveled.
2) At the start minimize player XP, maximize hero star/rune/level/abilities. You will gain access to 'My Dungeon' around level 10. Level 28 will introduce "Tower of Pwnage", a level scaled 12 PvP-style match daily event. Once able to clear the Tower and you have your roster maxed, push for a level gain.
3) Build-up PvP teams to complete guild "crown" quests. Best end-game pvp heroes as of January 2017 are Zen, M. Kira, Kozar, Shade, Viperia, Valkin, Aria (mostly to buff M. Kira), Furnace, Kai, Willow to complete nature hero guild quest, Pontifex, Pignius for crit boost passive, Grog Nogg for Kozar buff.
4) Once you can reliably complete all crown quests 7 days a week, join a guild that does 10500 crowns/week for the weekly 5x free heroic summon.
5) If you enjoy the game after a few days, you will want to consider putting down the $23 required for the VIP 3 Potion bonus--the best way to allocate that $23 can be discussed in responses.
6) Heroes used in end-game campaign play:
a) Campaign undead team: Zomm, Bromm, Overlord Exec (not my favorite), Yorick, Hansuke
b) Campaign Goblin Team: Bramble, Zurk, Nub Nub, Squinch-not as important as other three-, fully ascended Rocky (Nature's Fury Passive)
c) Useful Boss Mode heroes: Dagrund, Pignius, Daeris, Kobal, Indigo, M. Kira, Ember, Furnace
7) Save up 2700 gems for the 10x summon and wait for a key hero to be featured; Zen first priority for PvP & needs no ascensions, Astrid nice at start but requires both ascensions. Kai may be useful early on for defense. Kozar once Zen is unlock. Bramble and Zomm to form your PvE synergy teams.
8) Save resources and take advantage of the 2x token, 3x material, 5x Celestial Evo, and 2x nonor events. 20 gem token refreshes are worth looking into for the 2x token event.
9) Crystals, mushroom, mandrake root, pyre embers, and brimstone are material that will run short at end game hoard hundreds or over 1000 of each along the way to level 70--especially pyre Embers.
10) In general, the VIP portal is not as good a value as the Heroic Portal. The two exceptions are: 1) When you have most of the heroic heroes 6 starred 2) You get early access to 1 new hero at a time.
11) Earn at least 1000 honor from "PvP" each day and purchase the 250k gold packs. This needs to be done daily.
12) Clear challenge mode dungeons as early as possible for access to improved runes, pyre embers, Leonidus, and heroic portal hero tokens.
13) As a general rule (Torchy is better with HP), Defense>HP>Damage Reduction. Your defense should amount to about half your character's HP. Foozle has amazing references on many subjects, including stat balancing, if you are geeky like that.