What is wrong with that stupid demon brick (LoV #12)

[Atoli]

It's invincible.
No matter what I throw at it, it doesn't get hurt.
It comfortably sits at about 99% of it's health bar while surrounded by dozens of Yugiri's with attack buff up (and the extra strength against monsters), the 50% def down from hatchlings doesn't seem to faze it, even Hildibrand, the highest attack minion I own, WITH the atk/def buff up doesn't scratch it >.>

I thought that maybe I wasn't supposed to attack it, so I tried focusing on the adds, but only more ended up spawning and with my broken gates I could neither regenerate nor call new minions, so I'm pretty sure I am supposed to destroy the demon brick .-.
No enemy structures to destroy in that battle either.

I never had any trouble with the trials before, but this one just wasted 5 hours of my playtime and I still have no idea how to hurt that thing and I'm so sick and tired of it -.-
Is it only vulnerable to one certain minion or something? Since the fight is losely based on Amdapor, I can't really imagine it, but why else is it impossible to hurt it?

[Aurelle_Delacroix]

If I can remember correctly with what I did for that trial, I used a bunch of Minfilia's and like maybe a Minion of Light- White Mage or two just to keep them healed. You keep your main pack BEHIND the demon brick to keep attacking it while sending off smaller sections of Minfilia's to kill off the smaller mobs coming. It's fine if the demon brick breaks all three of your Gates. If you just keep management on the other minions, once the gates are destroyed the demon Brick sort of just sits there TRYING to attack your crystals in which you can just demolish it.

[Atoli]

I don't have the Minfilia minion, but that's not the problem. My problem was that the brick wasn't taking any dmg. Yes, it just sits there after it destroys the gates - but it's health bar stayed at 99%, never dropping, even though it was surrounded by my minions.

[Zohar_Lahar]

The fact the enemy has no gates to let you block its minions makes it very one-sided. Also, how is the demon brick able to move faster than any minion once it breaks a gate?

[Chiramu]

This trial would benefit greatly from an auto-lock on function in LoVM . My fastest minion is my Puff of Darkness but my poppets do more damage to the brick .

[PapanM]

I swarmed him with the Maelstrom mammets for their 50% defense reduction skill and it makes the demon brick much more manageable. They have one star speed, however, so you have to maneuver them slightly ahead of the boss to be able to keep up. Alphinaud is another option: though he only reduces defense by 13%, he has three star speed.

[Atoli]

So it seems I'm the only one who encountered the problem of an invincible brick.
I guess I'll write a bug report, then.

[Espritduo]

Were there other minions around him? If you send a swarm of your minions at the brick while it's at an aetheryte with other enemy minions, your minions will just attack whatever is closest to them, the Demon Brick usually being left out if there's a horde there. Try positioning your minions so their range of attack has the brick right in front of them and the other enemy minions on the other side. I had this trouble both with the brick and other bosses and had to re-position my minions to "persuade" them to attack the right target.

[Sir_Hermes]

Every challenge in LoV can be beaten with a single horde of Tomato Kings. 4 speed and OP attack... Use this strategy young Padawan and fulfill your destiny of easy RTS . (Thank You)!

[Atoli]

Were there other minions around him? If you send a swarm of your minions at the brick while it's at an aetheryte with other enemy minions, your minions will just attack whatever is closest to them, the Demon Brick usually being left out if there's a horde there. Try positioning your minions so their range of attack has the brick right in front of them and the other enemy minions on the other side. I had this trouble both with the brick and other bosses and had to re-position my minions to "persuade" them to attack the right target.

I had the brick alone in front of the last broken gate. He didn't move, he never lost HP. I tried countless times in those 5 hours and nothing ever happened, that's why I got so frustrated.
I tried again the same day in the evening and it worked just fine (and I went on to beat all the trials the same evening, never having the same problem as during that trial in the morning). Thanks for being the first answer that actually deals with my problem instead of giving out strategies that I didn't ask for xD
Since no one else seems to have encountered the same problem yet and it obviously isn't rooted in the brick only being vulnerable to a certain minion, which was my first thought about this, I'm 99% sure now that it was a bug (especially since it worked just fine later after logging back on, without any change to my strategy). I'll file a report, and this thread can be closed.

Thanks to everyone for trying to contribute and help