The simplest and most effective method for increasing the base depth of a mage's mana pool, the primary limiter of raw power, is for the mage to draw more mana into their pool than it can comfortably contain, then simply hold it, like holding a painfully deep breath, for as long as possible. If strained long enough, the mana pool permanently expands.

The technique has good synergy with white mana, although a white mage of low power would nevertheless need to use it sparingly, and would improve more slowly besides, since an already large pool increases in total size more quickly than a small one. The synergy comes from the intrinsic restorative properties of white mana, which work to heal any damage that the mana itself causes. The more mana a white mage already has, the more effective the healing. Since I could already hold enough mana to counter the damage as quickly as it happened, gaining strength was only a matter of time, patience, and pain endurance.

"Pfffft...." I breathed at a drop of sweat threatening to drip into my left eye. I could easily get rid of it with a purification-based cleaning spell, but that would use a little mana and drop me below the pain threshold. If it didn't feel like my skin was splitting, my bone marrow trying to escape, then I wasn't accomplishing anything.

What else could be expected? This technique was analogous to improving lung capacity by forcefully taking in more air than the lungs could hold, straining them until they permanently expanded, and then healing the damage. But, this felt more like an upside to me. It felt like justice.

"You should have done this whenever you had time," I admonished myself in a growl. "The damage heals immediately, anyway. No excuse."

The size of the mana pool isn't the only factor determining a mage's overall class. Control and knowledge of how to use the mana are also required, which come only with dedicated study and practice. But, it was the factor that I had been lack--

Izena turned toward me, terror on her face as her shield went down, her last sight being my shield increasing in strength as I stared back at her, having rerouted the mana invested in hers to strengthen mine. Soot and ozone and rot. Izena's black smudge on the ground--

Well, at least I was in no danger of forgetting exactly how strong the shields needed to be. I let the drop of sweat fall into my eye. The birds couldn't understand what I was doing.

My regimen was simple. This. Constantly.

After a few months, I decided to test my progress by casting three shields, one on me and two on my feathered friends.

"Right here, Skip," I sing-songed, placing a bit of tart red melon on my left knee, juice dripping seductively. Skip could always be counted on to skip where I wanted him to, head bobbing to and fro jovially, if I provided him with an appropriate bribe. And then stay there if I provided him with appropriate pets. Fuzzy would perch on my right knee whether I wanted her to or not, but I gave her some fruit to be fair. I got the sense that she disapproved of what I spent my time doing. Why not just "kaaaaruk, krooook" and be fuzzy with friends all day?

Shielding little birds wasn't a perfect analogue for humans, since bigger shields were less efficient and stable--relatedly, it was better to give small shields to many targets than to make a single big shield for everyone if possible--but it would be good enough. I could just make their shields unnecessarily large if I really needed to confirm my findings.

When everyone was in position, I ramped up to maximum power, divided the flow from my pool evenly into three parts, and formed three shields. Glistening cocoons of silver light surrounded all three of us, somewhat resembling curtains of water due to their imperfect transparency, with eddies of mana flowing chaotically in each.

I sat staring at the birds, the breeze playing with my hair in the shade of a fruit tree, waves breaking in the background. It was a picture of paradise, and Skip and Fuzzy were understandably oblivious to my frustration. I inhaled through clenched teeth.

"Not good enough, not even close. Not even close to enough for two, never mind three," I muttered stiffly. What was I expecting? I had barely been able to manage one adequate shield, after starting my life with a large mana pool and improving relentlessly for fifteen years. If it were so easy to triple my already legendary shielding ability in a few months, I wouldn't be here. None of this would have happened.

Months of suffering, nowhere close. I felt an irrational urge to beg the birds to forgive me for failing them, but resisted. It felt like that would lead to insanity. I would just renew my resolve and continue.

Wake up, draw as much mana as I could hold, sit or stroll around the peaceful island for hours while metaphysically cracking and resealing, an expanding egg, and repeat. For years I made incremental progress.

Sometimes, I considered how events may have unfolded on the mainland. With Oscanion defeated, the grand coalition army, our father's life's work, surely would have won decisively.

Oscanion's infamous mind domination created obedient soldiers out of those he captured alive, but without him to direct them personally, they were not particularly clever. His death may even have freed them, but I doubted it. More likely, they'd dropped on the spot. I'd tried healing the mindless, human and also beast, but there was nothing to heal, a healthy body without a pilot. They became irreversibly vegetative once my magic removed Oscanion's taint.

Those who fought for the tyrant willingly may have fought on, but most of those were cowards and bullies, bandits given a veneer of sanction, or misguided outcasts deluded into thinking they'd have a place in the new world they were making by unmaking this one. The majority would not take their master's defeat well, and there would be infighting. Plus, allied forces had the numerical advantage. Oscanion had only had as much success as he did because of a reluctance to unify that Azenum had overcome at last. Oscanion had his start as a single mage subverting one city! He could have been snuffed out immediately, when he was "just one rogue mage with unusual abilities and power."

The world was probably doing fine, and presumed me and my family to be martyred heroes. They were two-thirds correct.

I imagined returning, describing what had happened in those final moments, where I had been since. Even imagining it, the shame buckled my knees. "You chose to let them die to save yourself, then immediately fled to some paradise island where you played with fluffy birds all day? For years?! You could have healed those injured in the other battles! Many are dead now, or have been maimed for years, because you just couldn't cope?!" There would be nothing I could say.

I couldn't go back.

I drew an extra drop of mana into my pool so that the pain would spike a bit, and kept holding.

----

After ten years, I tentatively concluded that an effect I had initially theorized might happen was in fact occurring. I was aging too slowly. It did make sense: a powerful white mage holding maximum mana for most of every day should work to slow degeneration of any kind, including aging. My strength seemed to be enough to freeze me in time at the age of roughly 25 years. If my aging wasn't fully stopped, it was definitely slowed.

Thankfully, I hadn't grown much between the ages of genuine 20 and locked-in 25-ish, so my simple white battle tunic still fit, and purification spells kept it looking presentable. I hadn't considered that potential outgrowing-my-clothing problem when I had decided to just...leave.

But the strongest signs of the lock-in were mental. All of my memories were as crystal clear now as they had been at 25 or so, as though not a single day had passed since then. Time was not going to help me forget anything.