The 'Tag Embargo' and 'Tag Allow' features can be used to deny (Embargo) or permit (Allow) casting of abilities in your 'Cast Stack'.
Tag names must first be defined in the 'Tags' tab and configured with either a static duration or the duration of the triggering ability (+/- an optional duration adjustment). Additional options allow you to control how and to who the tag is announced and end the tag early if the ability leaves the maintained spell window [M].
Tag usage is configured on a per ability basis in the Cast Order on the 'Cast Stack' tab. Configured tags can be selected under the Embargo Tag and/or Allow Tag dropdowns, with a Type selected for each. The default (blank) type configures the specified tag to both listen and trigger in addition to options for Listen Only or Trigger Only.
Embargo Tags:
An ability in the Cast Order with an Embargo Tag Type set to Trigger Only will trigger the specified Embargo Tag on cast and announce it based on the options and duration defined in the 'Tags' tab.
An ability in the Cast Order with an Embargo Tag Type set to Listen Only will only cast if the specified Embargo Tag has either not been triggered or until a triggered tag's duration has expired.
An ability in the Cast Order with an Embargo Tag Type set to blank (both Trigger and Listen) triggers the specified Embargo Tag as above, as long as it meets the Listen Only requirements to cast. Note: By definition, an Embargo Tag of Type both (blank) can only cast and trigger as long as that Embargo Tag is not currently active.
Allow Tags:
An ability in the Cast Order with an Allow Tag Type set to Trigger Only will trigger the specified Allow Tag on cast and announce it based on the options and duration defined in the 'Tags' tab.
An ability in the Cast Order with an Allow Tag Type set to Listen Only will not cast unless the specified Allow Tag has been triggered and the duration has not expired.
An ability in the Cast Order with an Allow Tag Type set to blank (both Trigger and Listen) triggers the specified Allow Tag as above, as long as it meets the Listen Only requirements to cast. Note: By definition, an Allow Tag of Type both (blank) can only cast and trigger if the Allow Tag is already active.
Both Tags:
It is possible to configure abilities to use both Embargo and Allow Tags which follow all of the rules above.
Special thanks to Myzer for this write up.