How Powerful Is ShineGreymon? The Physics of Destroying Yggdrasil’s Tree Explained

In the world of Digimon Savers, battles often push beyond digital limits — but few moments stand out like ShineGreymon’s cataclysmic destruction of Yggdrasil’s Tree. What appears at first as a burst of cinematic energy hides a staggering level of real-world physics behind it.

This post takes a closer look at that scene, breaking down the scale, heat, and light output of ShineGreymon’s ultimate attack. From the massive size of Yggdrasil’s Tree to the blinding explosion that illuminated both Earth and the Digital World, we’ll analyze just how much power it would take to pull off such a divine-level strike.

Estimating the Size of Yggdrasil’s Tree

The first step is to determine the size of the tree itself. Based on what we see, its branches rise far above the clouds — placing its total height somewhere in the thousands of meters, likely between 1,000 and 2,000 meters tall. However, the anime never provides an exact measurement, making this estimation somewhat tricky.

So, how can we determine its height — and, by extension, its width and volume — without direct reference points?
The lack of concrete scale markers makes the task complicated, but fortunately, we can turn to a fan-created analytical tool: “Digimon Real Size Comparison.” This project offers an estimated height for the colossal tree, one that seems both reasonable and consistent with the visual presentation, making it a solid foundation for our calculations. 

Height, Volume, and Mass of Yggdrasil’s Tree

Based on comparative analysis, the Tree of Yggdrasil can be estimated to reach an incredible 810 meters in height — roughly on par with Godzilla from the MonsterVerse and Huanwumon, one of the Four Holy Beasts from Digimon Tamers.

With its height established, the next step is to determine its volume and mass. To simplify calculations, we’ll focus only on the trunk, which is roughly cylindrical in shape. This choice minimizes unnecessary assumptions and provides a cleaner estimate.

Using an average ratio where the trunk accounts for 70% of the tree’s total height, the trunk’s height would be about 560 meters, with a diameter of 600 meters — a proportion consistent with its massive visual depiction.

Applying the formula for the volume of a cylinder:

$$V = \pi r^2 h = \pi \times 300^2 \times 560 = 1.58 \times 10^8 \text{ m}^3$$

For mass, we’ll assume the average density of wood to be 1,500 kg/m³.
Thus:

$$M = 1,500 \times 1.58 \times 10^8 = 2.37 \times 10^{11} \text{ kg}$$

That’s over 237 billion kilograms of wood — a staggering amount of mass, highlighting the colossal scale of Yggdrasil’s trunk before ShineGreymon’s attack even comes into play.

Energy required to ignite and heat the trunk

The next step is to estimate the energy required to heat and ignite the entire trunk mass we calculated previously.

For wood at typical moisture content (~12%), a representative specific heat is about $c \approx 2300\ \text{J/(kg·K)}$
We’ll assume a minimum ignition temperature of 600 °C and an ambient temperature of 25 °C, so the required temperature change is:

$$\Delta T = 600 - 25 = 575\ \text{K}.$$

Using the mass previously calculated for the trunk:

$$m = 237,504,404,611\ \text{kg}$$

and the heat equation $Q = m c \Delta T$, we get:

$$Q = 237{,}504{,}404{,}611\ \text{kg} \times 2300\ \frac{\text{J}}{\text{kg·K}} \times 575\ \text{K} \approx 3.14\times10^{17}\ \text{J}.$$

Converting to TNT equivalent (1 megaton TNT ≈ $4.184\times10^{15}$J):

$$Q \approx \frac{3.14\times10^{17}}{4.184\times10^{15}} \approx 75\ \text{megatons of TNT}.$$

This result — ~3.1×10^17 J (≈75 megatons TNT) — gives serious weight to the claim in episode 33 that ShineGreymon’s attack could level a metropolitan area such as Yokohama. Even if the entire 430 km² city wouldn’t need that full energy to be devastated, requiring tens of megatons to ignite and heat the giant wooden trunk underscores the planetary-scale destructive potential involved.

Although this is only the first part of the calculation — the initial energy required to start combustion — there is another contribution we must add: the light (radiant energy) produced by the explosion, which was bright enough to illuminate half the Earth.

 That’s how all the Royal Knights in widely separated locations could see it — for example, UlforceVeedramon in Egypt and Dynasmon in New York — even though the blast happened in the Digimon World. This seems strange: if an explosion happens on one side of a spherical Earth, only that hemisphere should light up (just as the Sun illuminates only one side). 

The explanation appears in episode 39, where the Digimon World is shown collapsing onto every corner of the Earth — as if Earth and the Digimon World were flat surfaces about to collide, not spheres — caused by a rupture in the dimensional wall separating the two worlds and universes. That scenario explains how the entire surface of Earth could be illuminated.

To estimate the energy generated by the intense brightness, we’ll use the following parameters:

Illuminance of the explosion: comparable to bright daytime sunlight on a clear day — about 120,000 lux.

Conversion: $1\text{ lux}\approx 0.0079{\text{W/m}}^2$. For 120,000 lux, the irradiance is:

$$120{,}000 \times 0.0079 \approx 948\ \text{W/m}^2.$$

Illuminated area: we take the illuminated radius as half the Earth’s circumference, i.e. 20,037,500 m. Using that as a radius, the surface area of a sphere with that radius is:

$$A = 4\pi r^2 \approx 5.045415473123884\times10^{15}\ \text{m}^2.$$

With these numbers, the total radiant power is:

$$P = A \times 948 \approx 4.78\times10^{18}\ \text{W} = 4.78\times10^{18}\ \text{J/s}.$$

Interpreting this as an instantaneous radiative energy budget gives roughly $4.78\times10^{18}$, which is about 1,142 megatons of TNT.

This energy output would be per second. Based on the cinematic timing in the series, the light lasted for approximately 15 seconds, which brings the total energy to about 7.14×10¹⁹ joules, or roughly 17,064 megatons of TNT — an absolutely staggering amount of power.

Considering what ShineGreymon accomplished, this makes perfect sense. His attack obliterated BanchoLeomon’s body, a Digimon who once stopped a planetary collision, and also destroyed Daimon Suguru’s body — Marcus’ father — while he was possessed by Yggdrasil’s spirit. And, of course, he completely annihilated the colossal World Tree, the main server of the Digital World, itself a physical manifestation of Yggdrasil’s divine power.