Dark Angels are very tenacious, but sometimes this will overcome their better judgement and they will stubbornly refuse to move when it might be in their better interests to do so. To represent this, roll a D6 for each Dark Angels character, unit or vehicle at the start of the turn if there is an enemy model within 24", in sight and within range of at least one weapon in the unit. On a roll of 2-6 the unit can move normally, but on a roll of 1 the Dark Angels will stubbornly refuse to move and must remain stationary.
Dark Angels units that refuse to move may not move in the movement phase or the assault phase, but can shoot as normal. In addition, they count as being stubborn for the remainder of that turn and all of the following enemy turn, even if they are not usually classed as stubborn.
Important Exception: This rule does not apply to Ravenwing units and characters.
Errata — Chapter Approved: Codex: Dark Angels Q&A (v2.0): If an intractable Dark Angels unit is assaulted, loses, and falls back, it will never sweeping advance while affected by the intractable rule, but must consolidate instead.