Hey, first time posting here but I didn’t really see anyone making this point (outside of maybe JAlexander) regarding the current standard format. Current/recent Legend player (think 5000+, I’m by no means incredibly good), been playing since Beta, and previously a Grand Prix-level Magic: the Gathering player, so a lot of years of high-level experience as context.
Deck of Lunacy is a very strong card. We all know this because when we lose to it, we get completely overwhelmed by the advantage the card gives our opponents, and this is especially the case when it affects every card in the caster’s deck. We also know the effect is random because RTFC.
It seems like a lot of people here are upset at this card, and mage in general because of the randomness, and how it feels like you have no idea of what randomly generated thing is coming next which will kill you, and to a certain extent this is correct. However, what I don’t think people realize is that the randomness is felt much stronger by the DoL opponent than the DoL player, because of how randomness works in relation to power level and context. I’ll give an example:
Devolving Missiles is a strong card. Devolving 3 separate times is much more value than 1 mana should give, but this is “balanced” by the random effect of the Arcane Missiles style effect. As long as there is at least one additional target from what you want to hit, then the card *can* (but likely will not) do nothing. On the flip side, unlike Arcane Missiles, DMissiles has situations where *it cannot miss,* because it can’t hit players. This is where those backbreaking turn 2-3 DMissles experiences come from—a lack of randomness, which makes the card feel overpowered, because in this situation, it is. This is then where the context comes into play, because *whoever is playing the card decides when to play it* — in other words, the person playing the card gets to choose how much randomness they want to have when playing the card, meaning thy directly choose how strong the card actually is.
Going back to DoL, this is why it feels oppressive to play against, because the person who played DoL is the one deciding if they want to use the generated Negrand Slam to try to clear your board versus the Flamestrike they generated. Most of the time they will pick the option that suits the situation, so it always feels like they have the right answer. This is magnified by the sheer amount of card draw in the typical DoL deck which then makes it feel even more consistently like they always have it—because they’re incredibly likely to. They get to decide how to allocate the options given to them, which means they get to leverage *how broken* DoL’s rolls are.
This is ultimately to say that, randomness makes the problem worse, rather than actually balance an otherwise extremely powerful card, because the randomness doesn’t restrict the power, but rather the versatility of a card (DMissiles) This is also worse when the environment (deck) the card exists in reduces randomness (card draw).
tl;dr: Deck of Lunacy is overpowered but random, which makes it feel worse than just being overpowered.
I would say that one thing you forgot to mention is that currently, Deck of Lunacy's value is supposed to be offset by its randomness. Which currently, it does not do.
Regardless of which spell costs you have, the outcomes are largely good and there are very few bad spells to get.
So, on top of your point of letting the caster decide how and when to use their randomly generated spells, they are rarely holding bricks. Unlike before rotation, where your 7-cost spells could turn into Dimensional Rippers and your 3-cost spells could become Darkest Hour. Just to name a couple that spell mage has absolutely no use for.
Right now, in standard, the only real "bad" cards you can get are 1 at 8-cost, Guardian Animals, 1 at the 7-cost Commencement and 1 at 6-cost, Deck of Chaos. The rest at least can have some impact, depending on what else you get during the game.
So maybe in the future when they add more spells to the pool, the card will naturally go back to being "balanced" by true randomness. Or maybe when they nerf it we can see how it fares then. Some people in another thread suggested changing all spells into completely different ones and reducing the cost by (x), which would at least then make it so you can't build your deck to obtain the best results. (IE: more 7-cost, less 5-cost)