If the Atelier logo loads and you have a black screen, it is most likely due to the server being at capacity. And no, they don't have an error screen for this. You just get the black screen. Try again later when the server is not too busy.
Yeah it locks up if you open a new tab. You need to open a new browser and surf from that. The game has to run on a separate instance. And it needs to be the only thing running on that instance.
Consider adding a music opt-out checkbox in the pre-loading screen. If you check the box, it skips downloading all the music resources and the game plays without sound (and/or) music
Just in case anybody needs this information. The last boss is not very difficult if you chain stun him. Remember, you can also stun the boss with a lightning scroll and deal a massive amount of damage. You can take a maximum of 4 lightning scrolls into battle. Ideally the major amount of damage should be scrolls (fire lightning poison) and your omnislash. You're doing something wrong if you have to use your doubleslash. Also keep your magic armor going if don't feel confident in keep the chain stun going.
A quick win here would be an exp system. For example units that survive a battle will gain a star up to five stars. Each star will increase the effectiveness of the unit.
Hey would it be possible to have the 24 hour no-guild thing extended to both when you get kicked from the guild and if you quit a guild? People might be abusing the guild kick feature.
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Greetings! You will definitely need these resources in the future.