We only assume that destroying multiple universes
entirely is a tier 2 feat, only if they are defined by 4-dimensional space (ℝ^4). However for tier 3, or in particular 3-A , namely "
Universe level", it requires a destruction of any 3-dimensional (ℝ^4) space whose volume is equivalents to the observable universe's volume, ranged finitely. The problem here is that people often misunderstood the tier's name as the actual baseline requirement; 3-A is yet still in the framework of ℝ^3, but it somehow was put as a universe level (?),
if supposing that the cosmological model this wiki utilized as a standard is the
ΛCDM Big Bang model, which is composed of three main constants: cosmological constant (energy density that causes the acceleration of our universe, applied as one of the pieces of general relativity), cold dark matter (just another type of unquantifiable dark matter), and the ordinary matter (matter of our daily objects), then the tier 3-A shouldn't be named with "universe level" and only be defined by ℝ^3, because the structures already exceeded that level.