Yorbie: Episode One
12 Achievements
PS4
Stack Attack
Stack a weapon with 3 of the same upgrades
20.6%
How to unlock the Stack Attack achievement in Yorbie: Episode One - Definitive Guide
Noid
As you play the game you will come across weapon upgrade stations. You may spend cogs you've collected to upgrade your weapons' stats (Firepower, Fire Rate, and Total Ammo). You do not have to use the same stat for all 3 upgrades in general, but for this trophy you do.
Firepower is the only stat that actually has any really noticeable effect, so I highly suggest stacking all of your weapons with that.