Notable Game Interactions

Casted, non-cancellable
Immediate, cancels current action

Immediate, does not cancel actions

Damage upgrades
Damage is calculated by multiplying the final value with the upgrade value.

For example, 100 damage with five damage upgrades from the shop (+5% damage) will be calculated as 100 * 1.05 * 1.05 * 1.05 * 1.05 * 1.05, which equals 127.6. (This is slightly higher than if the damage was calculated after adding up all of the percentages, as 100 * (1.05 * 5) = 125).

Attack Speed upgrades
Speed is calculated similarly.

Attack period (p) is first converted to how many attacks the unit does per second (Hz) by taking 1/p. Then the number of attacks you do per second is multiplied by 1.03 for each attack speed upgrade. Taking 1/(number of attacks per second) will give us the attack period after upgrades.

Notice that this is not the same as taking p * 0.97 (shown in example).

For example, suppose we have a unit with attack period of 0.5. Taking 1/(0.5) = 2 gives us that the unit attacks 2 times per second. After getting one attack speed upgrade, it will attack 2 * (1.03) = 2.06 times per second. Getting two attack speed upgrades will give us 2 * (1.03 * 1.03) = 2.1218 attacks per second.

Converting back to attack periods, we have 0.4854 after one upgrade and 0.4713 after two upgrades. What if, instead of multiplying attacks per second by 1.03, we multiply the attack period by 0.97? We get 0.485 after one upgrade and .4705 after two upgrades.

Since the number of attacks the unit does per second, not the attack period, determines the DPS of the unit, multiplying number of attacks by 1.03 corresponds to a +3% increase in overall damage.

Derivation and equation for attack period after n upgrades (pn):



Cooldown Reduction
Cooldown reduction (CDR) is calculated in exactly the same way as attack speed, but with 5% instead of 3%.

Psion's Photon Charge ability alteration and Health upgrades
The Psions's maximum health after adding all Health upgrades is multiplied by 0.7.

Dash
Using Dash when not moving will not cancel skills that are being casted, and will still provide the period of invulnerability.

Toggleable skills
Toggling toggle skills (Ghost's Concentrate Power, Ghost's Concentrate Energy, Ghost's Cloak, Assassin's Concentrate Speed, Gunner's (focus firing thing), Spectre's Nyx Class Cloaking) will not cancel skills that are being casted.

(These are all non-targeting and have a 0 cast time. Don't think Psion's Psionic Pulsar is one, though)

Psion's Psionic Blast does not cancel skills, but sometimes if you spam it too fast, it will cancel Psi Drain only.

Focus Fire
Using Focus Fire while it is off of cooldown may cancel skills that are being casted.