http://www.wowinterface.com/download...fo.php?id=4102
This mod automatically sends a broadcasted message when the player casts or misses a Tranquilizing Shot. If the shot misses, it sends a different message than the normal one and displays a message on the screen warning the player that the shot missed.
Someday I want to update it to have an actual UI so the message can be more easily updated, and set an option to only broadcast when fighting against Magmadar.
To my knowledge tranq shot cannot be resisted or dodged by Magmadar, only straight up missed, so this mod doesn't take in to account those other posibilities. If this isn't the case, it isn't difficult to fix that.