Arise

There so many flaws with this that's not a Jin Woo Sung can fix it.

I'm not downvoting this because it's the D&D sorcerer spell equivalent of Jin Woo's shadow monarch class feature; making homebrew spells based upon something cool you saw in a show/game/frat party is A-OK in my book. I'm downvoting this because this is so lacking in mechanics it is a more of a concept than a spell ("you create undead of varying numbers and strengths" describes multiple necromancer spells), and because this is a cantrip of all things. If the purpose is to recreate the ability to add dead foes to your army whenever you want, that's more along the lines of an epic feat or high level class/subclass feature. Cantrips for magic user classes like sorcerers are supposed to be weak spells that help lower level PCs not be useless in a combat after casting 3 spells rather than represent anything that can be done repeatedly without eating up spell slots.

Beyond that, this has a listed casting time of 30 actions, which isn't a valid measurement. Spells with a casting time greater than 1 action should list a time period, such as 1 minute. 30 seconds is a rather odd casting time if that is what was meant, because that would require casting a spell with concentration for 5 rounds. I also can't tell if the duration of 2 minutes is a completely random mistake or if this means the shadow army only exists for a maximum of 2 minutes, at which point they cease existing. If the 2 minute duration and 5 rounds (or 30 rounds, if 1 action per round 30 times was the original intent) casting time is a deliberate attempt to make this less abusable despite not using spell slots, that's actually not a bad idea in principle, but it seems incredibly clunky and effectively renders it something not suitable for use during combat. 

I CAN totally sympathize with having an idea but not having the know-how to spit out a complicated chart (like a per-caster-level listing of how many dead can be raised and what their total CR or hit dice totals are) and putting it out there while still working on the nitty gritty (see my Half-Beholder's non-existent list of eye rays), but it just feels like the entire approach is fundamentally flawed. This really seems like it would be better suited as a high level spell - Shadow Army is certainly is not a low-level ability in the original source material. 

If you REALLY want to emulate a high level necromancer's ability to endlessly draft the dead into his undead shadow army, you are likely better off homebrewing class features that incorporate the rules for size and level of the army, and making a spell-like ability or feature-exclusive spell that simply includes the rules for attempting to enlist shadows in the first place - i.e. something like "range 10 radius, Verbal, 1 action: attempts to raise up to X hit dice worth of corpses that have been deceased no longer than a minute, making a magic attack/arcana check/persuasion attempt/something against each creature or group of creatures, with a DC equal to 10 + CR" to pull something out of the air without giving it too much thought.