Community studies suggest that the drop rates of common, rare, very rare, and Aegis shields are approximately 1 in 50, 500, 1500, and 1500 item rolls, respectively.
Mitigation and StickinessEdit
The base Mitigation of a Shield, as well as its hidden statistic Stickiness, is determined by its rarity.
|Rarity||Mitigation||Stickiness||XM to Apply|
If multiple Shields are attached to one Portal, each adds its full Mitigation value to the Portal's Real Mitigation. However, the damage reduction is capped at 95 % of the inflicted damage.
Shields have no effect on the Stickiness of other Mods attached to the Portal.
Links also increase the damage reduction. Approximately, 4 links mitigate like a rare shield; 11 links like a very rare shield.
Aegis Shield Edit
The Aegis Shield (previously AXA Shield) is a Portal Shield with the highest Mitigation and Stickiness of its class.
The AXA Shield item name and description strings were first discovered in the application package of Scanner version 1.65.0, and the item was released on December 15th, 2014 following a press release announcing the AXA insurance company's partnership with Niantic.
First-party Portals over AXA agency locations produced significantly more of the item when Hacked. For some time, Portals fitted with AXA Shields dropped the item more often, although this effect hasn't been borne out in recent community testing. As of Update 1.80.0, the hack rate of an AXA Shield appears to be identical to a Very Rare Shield.
As of July 9th, 2015, 600,000 players visited AXA agency locations and performed over 3,000,000 game actions on their Portals. Over 5,000,000 of the item were deployed in the five months following its release.
In 11 December 2017 with the release of Ingress 1.129.2, the AXA Shield was replaced with Aegis Shield and all inventories were immediately converted. (The same version also replaced the MUFG Capsule with the Quantum Capsule.)
Because a Shield's only role is to increase Mitigation, a firm understanding of the Real Mitigation computation is crucial to strategically employ the item. Shields, Link configuration, and the behavior and proximity of friendly agents configuration are all relevant to implementing a strong defense.
An attacker can trivially destroy an unshielded Portal, even if multiple agents are simultaneously recharging it. A well-shielded Portal is easier to defend through remote recharging and gives agents more time to react to their notifications. This protection will vanish when the attacker destroys the Shields, so the interim time should be used to mobilize a local agent to redeploy Shields as necessary.
Common Shields offer significant protection when deployed in multiples on Linked Portals. Two Common Shields deployed on a Portal with three Links offers about 85% Mitigation, significantly reducing the Portal's vulnerability to low-level XMP Bursters until the Shields break.
When determining which rarity of Shield to deploy, consider the density of Portals in the cluster. High-level Bursters will destroy Common or Rare Shields at a distance, leaving a wide swath of Portals defenseless. These areas demand redundant Shields, or the increased Stickiness of Very Rare and Aegis Shields, to hold against an assault.
Large numbers of Very Rare and Aegis Shields are critical elements of Ops and Anomaly gameplay. The extreme number of attacking agents can easily destroy an Aegis Shield every two or three seconds, and experienced agents will come to an event with hundreds of each.