In many ways, Aeon of Storms is incredibly similar mechanics-wise to Starcraft 2. But in many ways it is not. Mechanics can be very complicated and confusing to new and veteran players alike. This page is dedicated to explaining the complexities of how AoS works.
Strength, Agility, and Intelligence
These three attributes, seen to the right side of your unit information bar ingame, are the three main values that determine your Damage, Health, Health Regen, Attack Speed, Armor, Energy and Energy Regeneration. Each attribute is directly connected to two of these values:
Strength: Health, Health regeneration.
Agility: Attack Speed, Armor.
Intelligence: Energy pool, Energy regeneration.
In addition, each hero has a "primary attribute" that is either Strength, Agility or Intelligence. An attribute is determined to be the primary attribute of a hero because it is that hero's highest base attribute. A hero's primary attribute, in additon to scaling it's connected values, also scales the attack damage of the hero. Usually, a majority of the hero's skills will scale with it's primary attribute, though there are exceptions.
A primary attribute also usually decides how a hero will be played since they're determined by it's highest base attribute. Heroes with Strength as their highest attribute tend to have extremely high Strength. This boosts their Health and Health Regen far higher than an Agility or Intelligence hero would normally have, and therefore they're usually played at least partially as a Tank hero.
In AoS, there are three damage types: Spell, True, and Physical
Spell Damage: Includes some item attacks such as the Sunflare Gun and the majority of ability damage.
True Damage: A very specialized damage type that is dealt only by some items and abilities.
Physical Damage: Encompasses all auto-attacks from heroes, and some abilities.
How each of these damage types do damage is also very different:
True Damage: Ignores both Armor and Spell Resist. Essentially does direct damage to the health of the target.
Physical Damage: Ignores Spell Resist items, but is lowered by Armor.
See Attack Speed
Attack speed is defined as how fast your hero attacks. It is a vital part of any hero, though some benefit from it more than others. Attack speed comes with a tough balancing act of damage vs speed. If you focus entirely on building AS, you'll have no damage to back it up, and if you focus entirely on building damage, you'll have minimal attack speed to use the damage with.
Furthermore, for Agility and Strength heroes, attack speed takes on a secondary role to pure damage: Item effects. Many item effects depend on an autoattack to 'proc' or 'cause the item to activate'. Increasing attack speed will proc the item effect more, thereby increasing it's power. Intelligence heroes rely mostly on their skills, and so AS doesn't matter as much as it does to Agility or Strength heroes, though it is important.
The in-game attack speed "cap", or maximum speed at which specific heroes can attack, is 400%. However, this attack speed is not attainable by all heroes. Heroes with slower base attack speeds cap at slower maxed attack speeds.
The cap can be broken with timescale due to how timescale functions in Aeon of Storms.
Timescale increase the local passing of time for a hero possessing it. Unlike previous iterations of Timescale, as of v.1110, Timescale increases one's weapon speed and movement speed as well as everything else that is affected by time. Timescale actually goes as far as to shorten the time you spend using Recall. Due to it's incredible potential, very few items at the moment grant Timescale and those that do provide very low amounts to prevent certain heroes from abusing it.
With the combination of Time and Timescale, Cooldown Reduction was introduced as an alternative. Cooldown Reduction is more readily found unlike Timescale but only grants 1 thing: simple cooldown reduction. The cooldowns of things such as Recall or Fortify are not affected by Cooldown Reduction.
See Spell Resistance
Spell Resist is the attribute that allows your hero to take less Spell Damage from whatever source it may be. It scales with diminishing returns so you cannot reach 100% Spell Resist at any point in the game. In the current meta of Aeon of Storms, most heroes, including AD carries, stack Spell Damage items such as Lightning Rod and Isomorphic Pyre because it is the most efficient form of damage.
Armor is the attribute that allows your hero to take less Physical Damage. It is incredibluy easy to stack Armor in Aeon of Storms mainly because Agility heroes have passive Armor gain from stacking Agility but part of the issue lies in the fact that many items provide plenty of Armor. This has turned AD carries to stacking on-hit Spell Damage items for their main source of DPS. As a result, Armor is not an efficient way to counter damage with the exception of Critical Strikes.
See Critical Strike
Critical Strikes deal True Damage to the target in addition to the Physical Damage component of the original attack. As of v.1110, Critical Strikes are affected by Armor, making it the only form of True Damage that is affected by some type of resistance.