Giant animals are a staple of adventure fiction, especially in terms of “lost” valleys filled with prehistoric life, but this template can be used for “giant‐sizing” any type of creature.
The changes to the base creature depend on the number of size changes made to the monster, with each size change doubling the monster’s size:
|One Increase||+2 HD, +1 damage|
|Two Increases||+4 HD, +2 damage|
|Three Increases||+8 HD, +2 AC, +3 damage|
|Four Increases||+12 HD, +2 AC, +4 damage|
Each increase in size changes the monster’s size category to the next highest category (i.e. tiny to small, small to medium, medium to large, large to huge unless they are already huge, in which case they remain huge). Remember that an increase in Hit Dice also changes a creature’s saving throw values and increases their experience point value.
If you desire a common nomenclature for giant‐sized monsters, you can use the following:
Large Animal, Neutral (N), Animal Int.: HD 3; AC 13; ATK 1 bite (1d6+1); MV 40 (Climb 30); Save F11, R12, W18; XP 150 (CL 3); Special: None.
Huge Animal, Neutral (N), Animal Int.: HD 7; AC 15; ATK 1 bite (1d8+2); MV 30 (Swim 30); Save F7, R10, W15; XP 350 (CL 7); Special: None.
Huge Giant, Chaotic (CE), Low Int.: HD 16; AC 17; ATK Club (2d8+4) or boulder (2d8+4); MV 30; Save F3, R7, W8; XP 800 (CL 16); Special: None.
Huge Giant, Chaotic (CE), Low Int.: HD 18; AC 16; ATK 2 claws (1d6+4 + rend) and bite (1d6+4); MV 30; Save F3, R6, W7; XP 1800 (CL 19); Special: Regenerate (acid and fire).
License: B&T OGL