My current take on it would be...
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1) A reserve formation may choose whether or not to activate.

2) A reserve formation may rally in the end phase as normal.

3) A reserve formation which chooses to activate must attempt to move onto the board.  Much like a formation obligated to move out of an enemy ZoC or into formation coherency, it must attempt an action which will allow it to enter play.

4) A reserve formation which fails to activate takes a BM as normal for a failed activation.  It has the normal Hold options - move, shoot or regroup.  If moving onto the board is restricted (e.g. ZoC blocking the gate) that option is not available.  Shooting is not available off-board.  Regrouping could be used to remove the BM.

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#1 - It's been well-established that Eldar formations in the Webway get to choose when they come out, and are not forced to move onto the board immediately, so this is the same as the standing rule which has, so far, not caused any problems.

#2 - This is the same as the current rules for formations that are prevented from activating on their own - a formation loaded on an aircraft off-board, a formation loaded in a WE.  Like #1, it's worked fine so far so it shouldn't be changed unless some issue is exposed.

#3 - Mandatory entering of play upon activation prevents "burning" activations offboard as well as bypassing all the potential issues specific to regenerating Necrons.

#4 - This gives the player a small choice if the formation fails.

I'm fairly certain #4 is also the closest thing to a consensus from the last time the Eldar gates had this discussion.  The main point in that conversation (iirc) was concern over the availability of gates if a formation failed to activate, i.e. did that use the gate's capacity.  The conclusion was that the failed activation did not use up the gate's capacity which obviously means the formation is not forced to come through the gate.


The issue with #4 is with Necrons choosing to Regroup, which will allow them to Regenerate off-board if they fail.  I could see a Necron player with a badly bloodied formation off-board choosing to Retain with that formation in the hopes of failing to activate and Regrouping off-board (-1 for BMs, -1 for Retain).  That could theoretically have some tactical advantage over a Marshall/Move with the formation Regrouping on the board.

How often would a Necron formation be in a situation where it was really advantageous to fail an off-board activation?  Is that a big enough problem that we need to disallow it and change the rules just for the Necrons?

After all, a failed on-board activation has a similar reduced downside for the Necrons compared to the failed activations of other armies.  Barring some very specific tactical needs, that Regroup/regenerate is just better than the normal choices.  In that respect, a superior failed activation result while off-board isn't exactly bizarre.

We've been discussing it.  We don't have a final call on it.

We've been discussing it.  We don't have a final call on it.

My opinion is we need to address it as a general feature of the rules that would apply to everyone, and then address any Necron-specific deviation from that based on their specific special rules/exceptions.

On the Necrons, which ever of the three options are chosen, does "burning" activations by marshalling off-table cause problems - if so, could you write the Necron special rule to correct the issues rather than further nerfing the Eldar because this gives the Necrons an unfair advantage.