Arcane Guardian is an Arcane Enhancement that provides a 15% chance whenever the player receives damage to increase the Warframe's armor for 20 seconds.
Update 31.6 (2022-06-09)
We’ve adjusted the values of older Arcanes with the goal of making lower rank Arcanes more viable, and more desirable while collecting as a result. In short, there are three stats that each Arcane tends to have (speaking generally) -- for example, a percentage chance, a stat buff, and the duration of the buff.
Certain Arcanes increase all of these stats per rank (making them scale exponentially), but we are changing it so that only one stat is affected by rank (making it scale linearly). The other stats will now be at the max-rank value regardless of the Arcane Rank, thereby buffing lower-rank Arcanes as a result.
On Damaged: 15% (was 3%) chance for +150/900 Armor for 20s
Update 22.12 (2018-02-09)
Update 16.0 (2015-03-19)