The subject of colour coded dragons came up in the General RPG forum and as I had made a "universal dragon" for PF1 I decided to see if I could quickly whip one up for PF2. The dragons in the Bestiary are a bit of a hodgepodge and I do not have any guidelines for monster creation so I did my best to guesstimate good proficiency bonuses. The only addition I made which is a bit of a departure from the standard rules is that I gave my adult dragon resistance 10 to both bludgeoning and slashing damage for those armour-like scales. That could easily be dropped though, and they could be given damage immunity based on their breath weapon instead.

The Universal Dragon 2nd Edition, Creature 12
N Huge Amphibious Dragon
Perception +24; darkvision, scent (imprecise) 60 feet
Languages Common, Draconic, Jotun, Sylvan
Skills Acrobatics +20, Arcana +18, Athletics +27, Intimidation +25, Nature +18, Stealth +16, Survival +20
Str +7, Dex +2, Con +5, Int +2, Wis +4, Cha +5

AC 32, Fort +25, Ref +16, Will +24; +1 status to all saves vs. magic
HP 250; Immunities paralyzed, sleep; Resistances bludgeoning 10, slashing 10
Frightful Presence (aura, emotion, fear, mental) 90 feet, DC 31
Twisting Tail < Trigger A creature within reach of the dragon’s tail uses a move action or leaves a square during a move action it’s using. Effect The dragon makes a tail Strike at the creature with a –2 penalty. If it hits, the dragon disrupts the creature’s action.

Speed 40 feet, fly 160 feet, swim 40 feet
Melee > jaws +27 (magical, poison, reach 15 feet), Damage 3d10+13 piercing plus 3d4 poison
Melee > claw +27 (agile, magical, reach 10 feet), Damage 3d8+13 slashing
Melee > tail +25 (magical, reach 20 feet), Damage 3d8+11 bludgeoning
Melee > horn +25 (magical, reach 15 feet), Damage 2d8+11 piercing
Arcane Innate Spells DC 32; 4th suggestion; 2nd obscuring mist (at will); 1st charm (at will); Cantrips (6th) detect magic
Breath Weapon >> (arcane, evocation) varies (DC 33) It can't use Breath Weapon again for 1d4 rounds.
Draconic Frenzy >> The dragon makes two claw Strikes and one horn Strike in any order.
Draconic Momentum The dragon recharges its Breath Weapon whenever it scores a critical hit with a Strike.

Breath Weapons (choose one)
(fire) The dragon breathes fire in an 80-foot line that deals 12d6 fire damage, Reflex
(electricity) The dragon breathes lightning in a 80-foot line that deals 12d6 electricity damage, Reflex
(acid) The dragon breathes acid in a 80-foot line that deals 12d6 acid damage, Reflex
(fire) The dragon breathes a blast of flame in a 50-foot cone that deals 12d6 fire damage, Reflex
(cold) The dragon breathes a cloud of frost in a 50-foot cone that deals 12d6 cold damage, Reflex
(poison) The dragon breathes a toxic cloud in a 50-foot cone that deals 12d6 poison damage, Fortitude

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