Kaiju (Jap. “strange beast”) are giant monsters – although they needn’t be giant they usually are – that rampage cross the Earth, preferentially cities.
MSHRPG has some data on kaiju type monsters but it’s very unsatisfying. These are after all the pinnacle of pseudo-evolution, easily the largest entities heroes and villains are ever likely to encounter let alone battle.
Also Marvel characters such as Fin Fang Foom need to be given the awesome presence their size requires. Likewise any adaptation for eg the Dungeons and Dragons cartoon requires giant monsters to have giant powers!
The size related rules here could also be used for any other giant characters, other than those that shunt energy into another dimension like Pym Particle users. They don’t have the same applicable fantasy physics for obvious reasons. All giant characters that don’t use Pym physics and which somehow evade other effects of the square cube law should have the effects herein implemented.
POWERS AND EFFECTS COMMON TO ALL GIANT CHARACTERS
All giants (kaiju, titans, greek gods rocking it out etc.) have their height in feet as a Giant Rating. This Rating is given a power score like any other power or talent.
The rating is given from the tallest significant point on the entity to the ground, exclusing thin whip like tentacles antenna, etc.
For example a 50 metre (165 foot) kaiju sea lizard has 600 foot long tentacles. The tentacles are tiny compared to the bulk of the monster so it is easy to understand that the Giant Rating of the creature is Unearthly (165) and not based on the attenuated tentacles.
In a radius around where the character walks or crawls, the ground trembles and shakes with the equivalent of a minor earthquake. This automatically lowers every normal sized character’s ground movement rate by -1 CS for every 25 full points of Giant Rating the Kaiju character has. The Kaiju can also deliberately cause an earth tremor with a range equal to one step lower than its Giant Rating- for example an Unearthly Giant Rating has a Monstrous Earthshaking range. On a white Earthshaking power check the Kaiju does not slow the small characters in range by any greater amount than the automatic -1 CS. Green power check = -2 CS, Yellow power check = -3 CS and a Red power check immobilises all characters in range other than Kaiju for 2-20 rounds. People in vehicles have all effects doubled. Hovering and flying Kaiju don’t cause the Earthshaking effect unless or until they are on the ground.
Kaiju are so massive that they cause local weather deterioration around them, with a range equal to their Giant Rating. This weather deterioration causes high winds, cloudy skies and lightning. The lightning is random in effect but the total Weatherwarp effect is equivalent to a severe thunderstorm with random weather effects.
Any Kaiju can pick up any object that is two power steps or smaller in size than its own Giant Rating, automatically. Making a successful power check on its Strengh, the Kaiju can fling such an object with a range equal to the Kaiju’s Endurance rating.
GIANT STRENGTH ADVANTAGE – SHREDDING
Any Kaiju can make a Wrestling check on its Fighting score- in other words using its Fighting score to make a check as if Wrestling- to tear apart any inanimate object one step lower in size than its own Giant Rating. This tearing apart results in the object being ripped to pieces with a maximum number of similar sized pieces equal to the Giant Rating of the object, or for human and smaller objects 1-100 pieces.
Kaiju are so massive, with so much friction at ground level as they move, that they automatically cause Unearthly damage to all materials with which they are brought into contact, including buildings, all forms of restraint, concrete, steel, force fields, bare earth and even the seabed.
The above is a start, the main thing is to make big creatures awe inspiring, even in a superheroic game. They are meant to be existential threats. Under the existing rules Cloverfield would be a non-event; using some of the stuff above it becomes more like the movie.