A deck’s power is determined by how effectively its game plan can lead to victory, how fast it can get there, how good it is at preventing other decks from executing their plan, and how resilient it is when others are trying to stop it in its tracks.

We think this is the best definition of Powerlevel that we ever heard of. We also agree that grading a deck to a certain Powerlevelnumber from 0-10 or into level 1, 2 and 3 or thereelse is quite difficult, subjective, and not very percise. First, a large sample of games is needed, and second, the environment should be the same (that means the same decks as opponents), Decks may perform totally different when facing certain decks, example given: a Kambal Deck is the king when facing a noncreature deck, but will be less effective against a creaturebased deck like Chulane. Players will mostly rate differently and are not objective enough or have other scales to measure a deck. So power level is really quite relative.

Nevertheless, Anton’s criteria are good, and when you ask yourself: „would you like to play against your deck ?“ You can also at least a bit look at its interaction-abilities: if a deck has little removal, counters or abilities to remove artifacts or enchantments or creatures, it is less hindering, and thus lets other players involve at the game more freely. A deck, which totally shuts a player down from playing, be it landdestruction, countering quite every spell, discarding plenty of cards or thelike is simply not fun to play against, and also hinders involvement of others completely. (how good is a deck in preventing others from executing their plan or even from participating at the game at all.)

And lastly the pace: a cedh deck consistantly wins in turn 3 (have a look here at the cedh definition nowadays: http://tappedout.net/mtg-decks/list-multiplayer-edh-generals-by-tier/ ). „Normal“ Commander Decks have (don’t ask me where I found this number) an average cmc of 4.5 which is quite high. some decks will even just drop lands in turn 1 and 2, and play their first real spell (a Kodama’s rech maybe ?) in turn 3. So decks, which win on turn 3-5 are a totally other level than even a combo deck which has to collect 3-4  combopieces and needs 10+ mana to do the trick on turn 12+. (see above: how fast can a deck achieve a win?)

And last but not least, resilience and consistancy is also a criteria. A deck which can execute its plan every game because it is very hard to counter is very powerful. for example, Azusa, Lost but Seeking is very powerful as you don’t get priority and can’t respond to playing lands. Another example are planeswalkers or gods as commander: some colors have few or even none cards against them, so these type of decks are more resilient than others.

And decks, which once in a decade happen to pull off an evil combo are less of a threat than a deck which has more consistency and can build up its gameplan about every game.

So, to sum it up, these criteria can help you grade your deck better than counting the number of counterspells or creatures or cmc or wrath of gods in a deck. And: a honest talk about this and your gameplan and playstyle and goals before a game isn’t bad, either.