Hex = 10 miles

Castles are:
Dunstaffnage, Stirling, Duntrune, Dumbarton, Dunavertie, Ayr

Turn = Half a week.
By land move 1 hex. Can forced march 2 hexes but 50/50 chance of losing an element of stragglers. Each day halted allows 1 straggler element to catch up.
Brown hexes are impassable. Grey castles are passable if friendly. Otherwise the hex they are in and all adjacent are impassable. They can be approached only to besiege them.

By sea can move six hexes a turn.  Must end the move on the coast with the army disembarked. Roll 1d6 per hex moved.  Each 1 is an element permanently lost to shipwreck. From the first turn in September any roll of 1 is a storm with 1D6 of the elements lost and the rest driven ashore to the first hex to the east.
 
Supply.  If an army can trace a line to a friendly castle they are in supply. That line can be by 2 hexes of sea if Norse. If not supplied one element a turn deserts.

Sieges. Castles can be stormed or negotiated with. They can be surprised on the first turn an army arrives and taken on a roll of 5, 6. A failure loses an element. After that a 6 is needed and failures lose an element. Negotiations succeed on a 8+ with a plus one to the roll for each turn of negotiations after the first. Any assault breaks trust and no negotiation is possible.  

Armies start with 12 elements. They can be reduced by battle, siege losses, shipwreck, straggling.  Scots army is at Ayr and they hold Dunavertie, Ayr, Stirling, Dumbarton and also Bute (not a castle here).
Norse start on Gigha. If either side takes has an army outside Dunollie or Duntrune they join their side without a side and an extra element (3Bw) joins their army. 

Players must keep a note of their current army size (initially 12) and losses by straggling (which are temporary). 

Intelligence. After moving a player announces which area the army is in - for example Lennox, Argyll - and also the name of any castles it is besieging or has taken.

Victory:
Whoever wins a battle. The degree of victory depends on the differential of losses.
Otherwise:  Per castle held +1