The Heat Sink is a portal mod. Its multiple effects assist agents in Hacking the equipped Portal.
All Heat Sinks have the following effects:
- Reduces the Portal's cooldown, allowing it to be hacked again in less time
- Resets the cooldown timer for the agent who applies the Mod, so he or she can immediately Hack the Portal again
- Resets the burnout count for the agent who applies the Mod, so he or she can Hack the Portal additional times
Heat Sinks are available in Common, Rare, and Very Rare rarities, which affect the cooldown reduction the item bestows. Community studies estimate the drop rates to be 1 in 100, 500, and 5500 item rolls, respectively.
All Heat Sinks have 0 Stickiness.
Players often refer to Heat Sinks using an abbreviation. 'CHS', 'RHS', and 'VRHS' refer to a Common, {{rarity|R}, and Very Rare Heat Sink, respectively.
XM Costs
An agent of any level can deploy a Heat Sink by expending XM proportional to the item's rarity.
| Heat Sink Rarity | XM Cost |
|---|---|
| Common | 400 XM |
| Rare | 800 XM |
| Very Rare | 1000 XM |
Cooldown Reduction
A single Heat Sink decreases the cooldown time of the equipped Portal, reducing the time before an agent can Hack the Portal again. The effect applies to both allied and enemy agents. If an agent's remaining cooldown is less than the new cooldown after a Heat Sink is applied, the agent can immediately Hack the Portal again.
- Deploying one CommonHeat Sink decreases the cooldown time by 20%, or one minute for a portal with no other Heat Sinks.
- Deploying one RareHeat Sink decreases the cooldown time by 50%, or two minutes thirty seconds for a portal with no other Heat Sinks.
- Deploying one Very RareHeat Sink decreases the cooldown time by 70%, or three minutes thirty seconds for a portal win no other Heat Sinks.
When multiple Heat Sinks are attached to the same Portal, the rarest Heat Sink applies its full effect. Each subsequent Heat Sink's effect is halved, from highest to lowest rarity. The cumulative effect can be calculated using the following formula:
300 - (1-(1-h)(1-a/2)(1-b/2)(1-c/2))*300 h = Rarest Heat Sink decrease percentage a = Second rarest Heat Sink decrease percentage b = Third rarest Heat Sink decrease percentage c = Fourth rarest Heat Sink decrease percentage
For an example, a group of agents deploys 1 Very RareHeat Sink, 2 RareHeat Sinks and 1 CommonHeat Sink.
300 - (1-(1-0.7)(1-0.5/2)(1-0.5/2)(1-0.2/2))*300 = 45.56 seconds between hacks
Cooldown Reset
When an agent attaches any Heat Sink to a Portal, irregardless of rarity, he or she can immediately Hack the Portal again. This effect applies only to the agent who attached the Heat Sink.
Burnout Reset
When an agent attaches a Heat Sink to a Portal, that agent's burnout count for the Portal is reset and his or her burnout recovery timer is cleared. The agent can now Hack the Portal a number of times equal to its burnout count. A new four-hour burnout recovery timer will begin when the agent completes his or her next Hack on the Portal.
This effect applies only to the agent who attached the Heat Sink and disregards the item's rarity.
Strategy
The cooldown reduction is most relevant when a large number of agents have limited time to Hack a Portal. This makes Rare and Very Rare Heat Sinks crucial parts of "Powerhacks", or intensive hacking sessions, where the risk of enemy sabotage is high.
Because cooldown reduction serves only to reduce the total time it takes to burn out the Portal, the effect is irrelevant if agents have time to spare, if they can use the cooldown time efficiently, or if they can easily return after the burnout period elapses. Deploying a Heat Sink in these circumstances serves only to waste a mod slot.
The cooldown reset is useful for hacking the same Portal repeatedly in close succession, such as when acquiring Portal Keys.
The burnout reset synergizes well with Multi-hacks. Because the Multi-Hack's effects are applied to each burnout/reset cycle, its effect will be multiplied for the agent who attaches the Heat Sink. To maximize yield, the Multi-Hack should be applied first, with the Heat Sink applied only after the agent has burned the Portal out. Theoretically, an agent can perform 64 Hacks in 2 hours 10 minutes using this method with 1 Very Rare Multi-Hack and 3 Very Rare Heat Sinks.
If an enemy is attacking a Portal, an agent can continuously attach new Common Heat Sinks as the old ones are destroyed, so as to Hack the Portal repeatedly in close succession. In a pinch, an agent can even use a Flip Card to switch the Portal to the opposite side, destroy it, recapture it, and apply fresh Heat Sinks for additional Hacks.
Rare or Very Rare Heat Sinks attached to high-level enemy Portals are often telltale signs that enemies have gathered to rapidly 'farm' resources. Savvy agents will disrupt these Powerhacks and stake out the area to deny resources to the opponents.
Trivia
- Hypothetically, if a portal had 4 heat sinks installed that reduced the cooldown time by 99%, the cooldown time would be about 38/100 of a second.