A little shocked that there wasn’t a reward based on the guilds participation.
The Rally provides keys for the Raid and Battle. The Raid and Battle provides rewards for the entire Guild.
From the Update:
- Rally - Defeat an endless stream of monsters and earn individual rewards
- Raid - Attack an endless stream of bosses and unlock rewards for everyone in the guild
- Battle - Carry your guild’s banner into a Test of Might and unlock rewards for everyone in the guild
I do believe there are some basic requirements though like you have to participate in the Raid to earn the rewards but I think that is about it without re-reading the update more closely.