"It can glass a planet" is simply not enough information to get an meaningful data out of it.

It would be like giving a speed feat as, they traveled a distance in a single Planck Time. You can't tell how fast the thing was moving with just that information so for the purposes of /r/whowouldwin it is not necessarily usable.

This is the minimum shit you need to know is to properly quantify a glassing event. There is of course more information that could be relevant, but for the purposes of this rant I don't care about that.

1. The degree to which the area was glassed.

There is "glassing" as in they turned the top soil over.

Then there is GLASSING where they blow off the entire crust off the planet.

Both of those take very different amounts of energy. If the planet has some form of ecology back within a few years of being attacked, then the glassing was probably more like the former rather than the latter.

2. The area that got glassed.

Glassing an entire planet is going to require more energy than just glassing Australia which would take more energy than just glassing Luxembourg.

3. The time it took.

Even a ship with an fairly low power output (terawatts) can glass a continent given enough time.

Each doubling of the time halves the required energy output.

4. The amount of ships it took.

Two ships doing a glassing would only require half the energy output of a single ship doing the same thing in the same time.

So remember, when you venture out into the wide world of /r/whowouldwin, don't assume a glassing feat is a BIGGATON feat unless there is sufficient quantification to prove it so.