Size

Size, or Size Modifier is some undefined kind of attribute in AdVarTa. It matters only when creatures of different sizes battle and, as the mechanics are that fluid, there's not as much change from size as in other rpg systems. However, when it does matter, many things are affected by it, namely Base Damage, Damage Resistance, Evasion, Initiative and even Stamina mechanics.

Basically, each size category means a double in mass or a cube root of 2 = 126% in linear dimension. When specific mass or physical constitution are considerably different between two battling creatures, the GM should decide the size modifier depending on difference, but not stray from what's obvious.

E.g., an 1.8m - 80 kilogram human battling a 180 kilogram lion obviously means 1 size category of difference. An 1.8m - 80kg human fighting an 1.8m - 180 kilogram automaton, however, is more obscure, but ultimately it's best to consider how the attributes were ported. If they were compared to that human, then both are in the same size category. An analogous case is that 1.8m - 80kg human again battling some slender/gaunt humanoid of 2.3m and 80kg. If this creature is ported to the same size category of the human (where it could have about the same strength, toughness and blah blah), then both are the same size category. However, if the gaunt creature was ported accounting for its stats as a 2.3m humanoid (and thus would be expected to have lower strength/toughness than the "average for its size"), then there's 1 size category of difference between the two.

The recommended way to port characters to the AdVarTa system and ascertain its Size Category is to consider its relative human size (i.e. an android may be heavier, but always the same spatial size of a human). It's best to use mass instead of linear dimensions to consider size categories when the body form is considerably different (i.e. a lion and a human, or a submarine and a mecha).