Theoretically, this card might provide an excellent mechanic, but requires a very stable

situation to allow the result to ever occur.
If you can manage to lock your opponent up

with the controls that this deck would probably be built on, it might provide the edge

that you need. Notice that the clock allows you to add counters with your extra

available mana, but also that maintaining stability will generally require a certain

amount of such available mana. Adding counters this way will therefore be difficult,

probably a sporadic benefit. The mana that the clock provides, therefore, is

fundamentally sound, and I like the fact that the counter requires no tap. Ideally, you

would want your hand mostly played out when the clock strikes 12, to receive the most

benefit from it. So, I'd look into ways of staying active during play, rather than relying

on the typical "sit, counter and collect" strategies found in blue archetypes. The use of

Flash creatures will provide this, though there are scarce few with interesting abilities.

While too many Flash cards in Standard might make it too powerful, I could certainly

see the addition of some petty creatures that added functionality - Generally, I find that

common or uncommon Flash creatures are too costly, as well as boring. If I were to

investigate a deck design surrounding Midnight Clock, as is often the case, I think I

would be dissatisfied with the results. It might be great in theory, which is why I would

keep such a card in future consideration, but currently, I doubt it will stand up against

the more extreme archetypes. The added benefit of a new hand in the late game

would be irrelevant without just the right game-finishing elements. Doing it all, of

course, compromises your setup in this way or that - In this case, you can't let go of a

strong base of control cards, to keep things running smoothly long enough. I think the

game needs revision that would allow us to "do it all", but demand that the result be

masterfully directed to achieve it. A design that always does essentially the same thing

is not any sort of masterpiece, and you should never need to "believe" in your deck -  

Rather, you should know what it is capable of doing, and teach yourself how to

manipulate outcomes using it as a
tool, not a machine that yields predetermined

results. "Make the machine work!... No, no, no! What's wrong with this THING?!?"
Throne of Eldraine
ELD Artifact
ELD Blue