Keeping your hand still as possible, you stretch the shield, putting gradually expanding circles into the slot in the spell. It pushes Karina's hand outward, and she pulls back in surprise, though keeps watching with a curious expression as the shimmer widens.
When your shield reaches about the size of a door, it starts to falter. Trying to push it further just makes the mana fizzle away, though you could widen it to be a proper circle instead of a roughly person-sized oval. It's taller than you, though Frederic might not fit all the way behind it, not without ducking at least.

Enrique: "Please, no testing the limits of your spellcasting in my shop. I've had to repair my ceiling more than once due to overzealous wizards..."
You involuntarily glance up, and now notice several small holes and gashes in the plaster ceiling, filled in but still noticeable.

The shield vanishes as you withdraw the remaining mana. It didn't consume much to push back Karina's hand, but you can't really tell how hard she was pushing, or how bad a proper attack would be.

Enrique: "There are no training fields in the city, but just outside the walls is quite safe and no one should trouble you if you're not near a gate, assuming you aim away from the city~."
Leon: "Want me to shoot some spells at you to test?"
Leon waggles his eyebrows and gives a smug smile, earning a quick smack from Karina.

The two of you grin at each other, waggling your eyebrows in a display of dominance. Enrique watches with amusement, and Karina rolls her eyes.
Karina: "Ugh, boys."

[ Go test spells! ]
[ Other ]

~~~


The three of you head outside town, and make your way a few hundred feet away from the gate to a stretch of blank wall. Karina stands off to one side between the two of you, unsure who to stand behind for this test.

Leon: "Thankfully I'm not a willer, or this would be a lot harder with all the arm bandages. Ok, so that shield blocks physical matter right? I can start with that then."
He gently points a limp wristed arm at the ground, and a clod of dirt suddenly compacts, then lifts up into the air following his hand.
Leon: "Shields up, Gram. Whenever you're ready."

You make the shield and ready it in front of you, bracing for impact. Leon lifts his hand, aiming the dirt chunk at you, and then-
Like a brown blur, it darts through the air and explodes against your shield, lightly showering you in dirt. You flinch at the sudden speed and impact, but thankfully there was no recoil from the shield. Mana drain was... about, a fifth of the mana you put into the shield?
You could fill it a lot more than that if wanted, or feed mana directly to it with some focus. The amount you put in was maybe 1/6 of your capacity, so that's thirty shots like that you can block?
Leon: "How was that? That was about half strength. It can knock a grown man on their ass and knock the wind out of them like that, and break ribs at full power.
That was a clod of dirt too, if I had a sharp rock it could be a lot more dangerous."

Leon: "I don't think this spell works well with metal, just dirt and stone. Maybe a little bit, but haven't tried it yet. Probably stone spikes at like, an adventurer gear store though, that's just as good.
Ready for other elements? Gonna try water and air, then the more exciting ones!"

Leon starts getting into it, testing the other spells at his disposal on your shield.
Water goes predictably, about the same amount of mana drain as earth. Air ends up weaker, maybe about half or 2/3 as much drain as the first two.

Leon: "Alright, next up is electric."
Karina: "Please be careful... I don't want to have to heal you dummies."
You ready your shield, full up on mana, and Leon sends the electric bolt your way. It zips through the air, a slight crackling and a few tiny sparks the only indications of it. Then, it hits the shield. You feel a mana drain, a smaller one like the air spell, and then a split second later several arcs of electricity jump through the air around the shield, curling from the air in front of it all the way around to behind and into your arm. The shock makes you lose concentration and the shield drops, while you yelp and jump backwards shaking your arm.

Leon: "Shite."
Karina: "aaaAAH! Gram, are you okay?!"

There's a strong tingle, but seems like no permanent damage. All the fingers still work fine, and didn't feel like it traveled further than your elbow.

Leon: "I, seriously didn't expect that to happen. I knew electricity could arc, but I didn't think it would go around and back into you like that.
Wait. Oh. Ohhh. The spell might've, gone through the shield intact. And then, re-formed some of the charge on the other side."
Karina: "Dummy!"

Karina puffs up and begins lightly but angrily beating on Leon's back, while he sheepishly looks your way.
Leon: "Whoops. Sorry, Gram. You uh, still up for the others? I think we can skip fire, but I am interested in seeing how light and dark interact, if you're up for it. Ice too actually."