To plug my own game for the umpteenth millionth time (tbf Im currently in the steady grind of writing it so its always on my mind anyway), I have Horde mechanics that form the core of my mass warfare mechanics.
Using them, you can take a statblock for a single goblin and scale it up as high as 10,000, if you want, and you can do it without even needing another statblock. All stats, abilities, etc are easily scaleable and all you need to do is run the math once and have it referenceable. (And I plan on making it so my blocks have the space apportioned to do this)
And the best part is, it still feels like you're actually fighting with entire armies, and indeed, player characters are being designed to where you can take on these Hordes as individuals, or while integrated into your own Horde, and again its all very very smooth.
This lets me do Necromancers that actually feel like proper Overlord style Dark Lords, and as it happens helps Martials (who are already awesome in my system to begin with) feel hella badass, given fighting a Horde by yourself translates your damage into you cutting down foes by the dozens.
This is why my strongest Barbarians can deal up to 6d12 3x in a row on one turn, with just plain low-level weapons. Because once you get there, you're either facing down these Hordes, or swinging into proper endgame monsters that threatent continents.
Interestingly, though, is that while my game will be much higher octane than 5e is, its magic is actually technically going to be more powerful and dramatically less so at the same time. Namely because while combat magic is great and reliable, any other kind of magic isn't.
Even as a 30th level master with maxed skills, you're not guaranteed to always be able to solve a problem, unless the solution is to destroy the problem. You still progress and become very adept at utilizing improvised magic (there are very few utility spells you can explicitly weave yourself; most effects you might want have to be improvised), theres always a chance of it backfiring on you. And to use those few explicit spells that you can weave takes time, effort, and learning achieve. Whereas blowing naughty word up is easy even for toddlers
. (Which if your curious has a lot of deep lore that solidifies why magic is so inherently dangerous, and why the Mystics are a distinctly different kind of "magic" from the conventional)
