Pretty much, yes, but infinate isn't quite true.

(The magic system isn't DnD, so I'm spending way too much time making up a lot of shit here to give a general idea that no one really asked for. (And because its fun to brutely mash one magic system into another)).

Let's say your average mid to high level mage has 100x spell slots (and for now assume all other stats are also equal). In this system, there are no spell levels. Instead, more complex spells require more slots to be used at once.

The basic defence and attack spell are 1 to 10. 1 defence spell blocks 10 basic attacks. However, you can't attack and defend at the same time, and 1 defence is only for a small area. Full 360° coverage would cost a lot of slots per second. You conserve slots by precicly blocking the opponents spells as they come.

To break the defence you need to to be able to hit it really hard and follow up before they can cast more defence or counter attack. To do more damage in a spell, it costs more slots. This is where things like the other stats, skills, refelx time, unique spells, and combat stratagy become deciding factors in fights. Slot count also varies, a young mage might start of with one slot, but can become a very high level mage with 300 slots.

MC has 200 slots to start with and trained to get a very fast cast per second rate for both basic attack and defence. They are so proficient in the spell, it's the equivelent effort of you or me walking.

While MC's magic mistle does little damage, they can cast the spell 20 times in a second from multiple directions. This forces opponents to use up all their slots to defend until they run out or get overwhelmed by the numbers. The only defence is to do 360 defence, which can't be maintained for long. (For simplicity sake, assume all the magic is a one shot kill. If you don't defend or dodge, you die).

To make things more fun, MC has no idea they are insanly strong because their only reference growing up was their mentor who has the 5000 slot cheat code.

Yes, I am over thinking this. And yes, I should be sleeping right now.