Unwavering Phalanx

Use this Stratagem in your opponent's Shooting
phase, when a TS RUBRIC MARINES or TS
SCARAB OCCULT TERMINATORS unit
from your army is selected as the target of an
attack. Until the end of the phase, each time an
attack is made against that unit, subtract 1 from
the Damage characteristic of that attack (to a
minimum of 1). If that unit contains 5 or fewer
models, this Stratagem costs {1}CP: otherwise
it costs {3}CP.