Alien (CR +1)
Alien creatures dwell in the furthest planes, but can be summoned using spells such as summon monster and planar ally. An alien creature's CR increases by +1 only if the base creature has 5 or more HD. An alien creature's quick and rebuild rules are the same.
Rebuild Rules
Senses The creature gains darkvision 60 ft.
Defensive Abilities The creature gains damage reduction and energy resistance as noted on Table: Alien Creature Defense.
SR The creature gains spell resistance equal to its new CR +5
Special Attacks The creature randomly gains (roll 1d6) one of the advantages from the Alien Advantages list.
Table: Alien Creature Defenses
Table: Alien Creature Advantages