One unit may
stack under another unit. Two or more units grouped
in this way are referred to as a stack.
Stacks move together and fight together. Here is a stack of four units:
Law Netexus , accompanied by: Feasel the Wicked  Drakkar the Trader  Alion Krysaka 
Law Netexus is the stack leader, the top-most unit in the stack.
Only one level of stack depth is shown, so all that can be determined from the location report is that Feasel, Drakkar and Alion are stacked somewhere beneath Law Netexus. The exact arrangement of stacking bonds is not shown.
Feasel might be stacked under Law Netexus, with Drakkar and Alion under Feasel. Or Feasel, Drakkar, and Alion may all be stacked directly beneath Law Netexus.
Generally, such internal arrangements are only important when the stack breaks up. If Drakkar is stacked beneath Feasel, he will stick with Feasel if Feasel drops out of the stack. But if Drakkar were stacked beneath Law Netexus, he would not follow Feasel if Feasel unstacked.
If Law Netexus issues a
move order, the entire stack will move.
If, however, Feasel issues a
move order, he will first drop out
of the stack before moving.
Similarly, if Law Netexus engages combat with the
all characters in the stack will fight together. If one member of the
stack is attacked, the entire stack will respond in defense.
Multiple levels of internal stacking can be useful if one wants several stacks to join together for a while, but then split apart later into their old arrangements.
Ocean ships may not be stacked together. There is no way to cluster ships into a fleet.