In order for you to play Dragonero on Linux with minimal graphics settings, your computer must meet the following requirements
Operating System:
Ubuntu 18.04
Processor (CPU):
Intel Core i3-3240 (2 * 3400) or equivalent
Memory (RAM):
8 GB RAM
Graphics Card:
Open GL 3.2+ Compliant
Storage:
10 GB available space
In order to play Dragonero on Linux with maximum graphics settings, you need a computer with a configuration no worse than the following
Operating System:
Ubuntu 20.04 or equivalent
Processor (CPU):
Intel Core i5-3470 (4 * 3200) or equivalent
Memory (RAM):
16 GB RAM
Graphics Card:
Open GL 3.2+ Compliant
Storage:
12 GB available space