Here are my recommendations for using the phalanx capable units for greece, macedon and selucid as they appear in the game,

Phalanx units are not fast moving, they wont blitz through the enemy line in a heart beat (they are heavy troops, not shock cavalry),
But they will decimate most anything that gets in their way.

Phalanx Troops were a Steam Roller, they did punch through enemy lines, but they did not do it quickly.


To Get the Most out of Phalanx Units
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Turn Guard Mode off,
Phalanx units will never persue routing troops very far at all anyway, even in aggressive mode. IF you want them to persue a routing unit take them out of phalanx and order them to chase.

Keep your phalanx units in a cohesive line (open field battles)

If you take a unit out of phalanx to move/redeploy quickly, Then give them a few seconds to reform before attacking

Pick your targets and double-click

Protect the flanks
Protect the End of the line with cavalry and heavy infantry
Protect any Gaps that may appear between Phalanx units with nimble troops, they need to be able to move quickly to guard the flanks of your Phalanx,
You dont need to try to engage anything, just stand in the gap so nothing can get at the flanks.

IF Your army leader is in a Phalanx unit be very carefull, watch where The Actual Leader Figure is standing and try to keep him out of a Phalanx/Phalanx confrontation
- he only has a sword,
- he will try to charge the wall of spears,
- he will wind up poisoning the carrion birds...

Avoid Terrain Obstacles where possible, they will disrupt formation and disrupt cohesion of a line of phalanx units.
IF you must pass through a terrain obstacle pre-order your line to stop immediately after the obstacle to allow your line to remain "solid".

I pin the enemy main line with my Phalanx units, knowing they will hold long enough for me to go round the flanks and deal with skirmishers and missile troops, then to fall uon the rear of the units the phalanx troops have pinned.

I also use Phalanx units in City Assaults,
I make 3 breaches in the wall, I time them so the first breach is the gate and make one additional breach EACH side of the gate some 15 to 30 seconds later.
I push a Phalanx into the Gate to attract and pin enemy troops, then push something else through the breaches to either side and sandwich the units pinned by my Phalanx.
Then I use my Phalanx units to guard the gate area, and everything else moves into the city.


How to deal with an enemy Phalanx.
Simple, use a reasonable defensive unit as a "pin" on guard mode to engage the Phalanx, and hit the Phalanx from the sides and rear with cavalry.

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What can go wrong

If you leave Guard Mode On for Greece, Macedon and Selucids the Phalanx units become dancing fools.
You can enhance and prolong dancing fool mode by clicking behind the enemy line rather than a direct attack on a unit.

PLEASE NOTE results Cannot be guaranteed if you have installed ANY mods that you yourself did not make, You have NO guarantee what the mod-maker may have tweaked and forgotten to mention.
and if YOU made a mod make sure you did not tweak or alter ANY units.