User blog:Epsilon R/Black Clover calc

Average surface of a 2-room house: 45m^2

Assuming the house is a square, its side would be 6.708203932m

House = 6.71m = 23px

PoV = 881px

Angle = 2 atan(tan[70/2]×[23/881]) = 2.094512563°

Distance = 183.53m

We will use this distance as an average size for the trees

Tree = 183.53m = 23 px

Fireball = 327px = 2 637.7526086957m

Volume =

74416553604.153 (× 20.9%) = 15 553 059 703.267 m^3

O2 density is 1.3311~1.42902 kg/m^3.

Low-End:

Mass = 15 553 059 703.267 × 1.3311 = 20 702 677 771.018 kg = 20 702 677 771 018 g

32 g of O2 = 418kJ

E = 20 702 677 771 018 × 418 ÷ 32 × 1000 = 2.70428728+17 J or 64.6340173002 Megatons

High-End:

Mass = 15 553 059 703.267 × 1.42902 = 22 225 633 377.162 kg = 22 225 633 377 162 g

32 g of O2 = 418kJ

E = 22 225 633 377 162 × 418 ÷ 32 × 1000 = 2.90322336E+17 J or 69.3887036303 Megatons

Final Tally

 * Low-End: 2.70428728E+17 Joules or 64.63 Megatons (City level+)
 * High-End: 2.90322336E+17 Joules or 69.39 Megatons (City level+)