Ok so Slattern is a lot taller and longer so Slattern wins in height and length, 2.0
Godzilla is about 90000 tons and Slattern is about 16000 so Godzilla wins in weight, 2.1
Slattern has more melee weapons, 3.1
Slattern is stronger, 4.1
Godzilla has more lethal weapons, 4.2
Godzilla has a bunch of heavy allies while Slattern has infinite light allies so no allies are allowed.
Slattern has more experience, 5.2
Slattern has a higher kill count, 6.2
Slattern is faster, 7.2
Slattern is more agile, 8.2
Godzilla has more balance, 8.3
We will allow each kaiju to have 2 allies only.
Kong and Mothra are bigger than Raiju and Scutter, 8.4
Kong and Scutter have an = amount of durability, Mothra and Raiju have an = amount of durability but in different ways, Mothra is soft and practically made out of dust and chitin, soft body and hard legs, Raiju is just thin layers of skin half way and the other half is hard skin, thick head armour, fragile body, tie in ally durability.
Kong and Scutter have the same amount of weapons, but Scutter’s are more lethal, Mothra has a to more weapons than Raiju, this would be a tie but Mothra has 7 weapons while Raiju only has 2 so Kong and Mothra win in weaponary, 8.5
Slattern has a higher bite force and bite impact, 10.5
Slattern is more durable than Godzilla, 11.5
Both have taken a nuclear bomb to the face and survived,11.5
In the game Slattern has been able to take on 4 enemies at once, but that is an unfair advantage, 11.5
Godzilla has a stronger tail, 11.6
Slattern has longer and sharper claws, 13.6
Godzilla is used to fighting on land so Godzilla wins in terrain, 13.7
Godzilla has fought in snow and ice before so Godzilla has more fortitude, 13.8
Slattern wins.