How did he upgrade a regular weapon to level 12?

[Keknutui]

Seriously, I searched everywhere, but I still didn't understand, I thought this opportunity appeared when pumping at least one boss weapon to level 12.

[Electroely]

37 minutes ago, Keknutui said:

Seriously, I searched everywhere, but I still didn't understand, I thought this opportunity appeared when pumping at least one boss weapon to level 12.

I don't believe it is explained anywhere in the game.

Once you clear a super frenzy (or get a boss weapon? I'm really not sure if you even have to do either of these things), you unlock a Support gem called the "Teffressence Container Gem". Clearing a Super Frenzy run with this gem on a regular weapon upgrades it to Level 10 (granting it a third gem slot) and allows further upgrades to Level 12 using Corestones and Fortifying Ingots.

[MrMyther]

1 hour ago, Electroely said:

Once you clear a super frenzy

Fairly certain they aren't locked at all, aside from actually accessing the gems table.

[Instant-Noodles]

10 hours ago, MrMyther said:

Fairly certain they aren't locked at all, aside from actually accessing the gems table.

Teffressence Container Gems are actually locked.  They can't drop until you have access to a Super Frenzy.  So, the requirement is to complete Frenzy 3 on one of the three maps that currently have Super Frenzy available.

@Keknutui This is what the gem looks like:

[Keknutui]

11 hours ago, Instant-Noodles said:

Драгоценные камни из контейнера Teffressence фактически заблокированы. Они не могут выпасть, пока у вас не будет доступа к Super Frenzy. Итак, требуется пройти Frenzy 3 на одной из трех карт, на которых в настоящее время доступна Super Frenzy.

@Keknutui Вот как выглядит драгоценный камень:

Thanks, I've already figured out the problem. And thanks for your channel, where I usually choose what to wear to the boss)