# Triggering when counter placed on other counter

**URL:** <https://forum.vassalengine.org/t/triggering-when-counter-placed-on-other-counter/3541>\
**Category:** Module Design\
**Created:** [December 31, 2010, 5:48pm UTC](https://forum.vassalengine.org/t/triggering-when-counter-placed-on-other-counter/3541 "2010-12-31T17:48:14Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![John\_Boone](https://forum.vassalengine.org/user_avatar/forum.vassalengine.org/john_boone/32/6741_2.png) [@John\_Boone](https://forum.vassalengine.org/u/John_Boone)\
**Post date:** [December 31, 2010, 5:48pm UTC](https://forum.vassalengine.org/t/triggering-when-counter-placed-on-other-counter/3541/1 "2010-12-31T17:48:14Z")

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I would like to fire off a trigger that affects counter B when counter A is placed on counter B.

What is the simplest way to do this?

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**Author:** ![Tim\_M](https://forum.vassalengine.org/user_avatar/forum.vassalengine.org/tim_m/32/2_2.png) [@Tim\_M](https://forum.vassalengine.org/u/Tim_M)\
**Post date:** [December 31, 2010, 9:03pm UTC](https://forum.vassalengine.org/t/triggering-when-counter-placed-on-other-counter/3541/2 "2010-12-31T21:03:11Z")

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use a Trigger Action trait to execute a counter Global Key Command trait:

Trigger key command CTRL 1 executes CTRL 2

GKC key command CTRL 2 executes CTRL 3 Property Match Field: LocationName = $LocationName$ && BasicName = NameOfPiece  
CTRL 3 is on the receiving piece and does whatever…

This is the easiest and most basic way.

Sorry for edit - you mentioned when stacked on a piece. So for this to happen we specify that the triggering piece use its current location as the only place where it can affect another piece by using the LocationName = $LocationName$ property also (there is no property for “stacked” components although it could be useful as in this case

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**Author:** ![John\_Boone](https://forum.vassalengine.org/user_avatar/forum.vassalengine.org/john_boone/32/6741_2.png) [@John\_Boone](https://forum.vassalengine.org/u/John_Boone)\
**Post date:** [January 1, 2011, 1:12am UTC](https://forum.vassalengine.org/t/triggering-when-counter-placed-on-other-counter/3541/3 "2011-01-01T01:12:43Z")

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Thanks Tim,

I had to add the map trigger to send a CTRL 1 when the first piece is moved on to the map to get it to work like I wanted it too.