The Guild Banner Designer is a replica of the Guild Emblemer: you can design your cape, change patterns, colors and emblem with the same options like the one in Guild Wars. Also, you can add a cape trim and export your creation.
The other 7 trim colors (blue, green, orange, pink, purple, red and obsidian) can now be picked, have fun!
If no one is the boss, killing another player makes you the boss, giving you -20 armor but the following bonuses: +33% attack speed, +33% movement speed, -33% skill activation time, +3 Health regeneration, and +1 Energy regeneration. If you die, you stop being the boss. If another player killed you, they become the boss.