Hi, I'd like to present You all my idea of event.

TIME:

Every Sunday, every 8 hours there would be guild town invasions.

SYSTEM(how it would looks like):
Each invasion would start from Town portal, which U enter guild town. Guild town then may be closed to other players than guild ones.
Each invasion could contain 5 waves of mobs.
Each wave would be harder: 1st wave 10lvl, 2nd 20lvl, 3rd 30lvl, 4 40lvl, 50 50lvl. So that everyone could get part in it. Eventually system could count average lvl of all guildies and send 5 waves of same lvl mobs but each wave with more enemies (f.e. every lvl50 waves would be:
1st wave 20N5E1B, 2nd 40N5E1B, 3rd 40N10E1B, 4th 40N10E2B 5th 50N15E2B or smth like that ||| N = normal, E = elite, B boss).
Numbers I'd suggest for each wave could be 20 normal mobs, 5 elites, 1 boss if you consider 5 grade waves (10lvl,20lvl etc. ). All at once. Those numbers may sound silly when u consider 150ppl guild, but tbh which guild has 150 or 100+ members online all the time.
Everyone who gets part in it could get character & class exp. It's only Sundey 3times/day so not big deal i guess
Again types of mobs and bosses i'd leave to GMs decision, to make it more interesting could be diffrent mobs and bosses with diffrent skills and make it all random so U never know what to expect.

WIN / LOSE :

Maybe firstly I'll say how to lose. Nothing special with it, put Crystal behind Statue or in front of it and when destroyed , U lose. Hp of it i have no idea depends on fighting system (only lvl 50 mobs or 10,20,30 etc)
How to win? Kill all mobs

REWARDS:

I have clearly no idea if mobs here would give any items.
I was thinking about more goods for whole Guild.
Every monster u kill, no matter if elite/ boss:
each 10lvl gives 200s to guild funds
each 20lvl 400s, 30lvl 600s, 40lvl 800s, 50lvl 1g
I know that this would be too good for high lvl guild with many 50lvl players considering 5 waves of 50lvl mobs, thats a lot of gold for guild but hey: Once again it's only every Sundey 3times/ day. Since for lvl 6 guild U need 54.000 gold, it's still not much, i guess ;D.

Final reward would get Guild Leader to his mailbox which would be NPC Box or Statue with better buffs like 10% or Loot 10% i don't know here yet. NPC Box seems fair cause they lasts for 1 week or less, but again it's all about GMs decision.

And thats it,
Thank You for your attention

P.S. Sorry for english if there are some mistakes ;P
Ofc it's just idea, everything can be changed here

Good Idea it deserves a +1 from me

But!, instead of the guild leader receiving an uber prize let whoever participate get something good. Dye colors and or a stack of orange wepon boxes (since the item you get in those boxes are completely random and are not the easiest to get) Once a week would be awesome and id vote for it to be on Saturday cause Sundays we have 2x class experience or whatever.

Uhm i forgot to add that boxes or statues which guild leader will receive would be NT, so he'd have to use it in town. Even if guild has npc in town that got from event box, leader could keep it in guild warehouse until town's one gonna leave.
Saturday seems good for me aswell, even hardcore players could participate in all 3 invasions not thinking about monday and their job ;P
And items for players, its hard to do it fair somehow. Until there gonna be thing like SQUAD containing few parties cause now u can create few parties, still there will be one leading with GL and they would get all stuff. For me its hard to solve rewards for every player joining invasion, thats why my first plan was to reward whole guild.

This sounds like an excellent idea. It would also help the struggling levelers who can use that extra boost. Especially that Lv40+ people who can barely get exp unless they do massive GQs. And speaking of which, maybe add a better chance of getting valuable items for the more GQ points you have? That would inspire more people to help out the guild.

Hmm yeah totally forgot about fame points for guild.
Ofc could give 1 fame point to guild for each monster killed, wouldnt be much, and still nice. Also there could be special guild quest for that invasion that'll give 10pts, but when like 20members give quest back its 200 fame points for guild. Guess its nice idea, although those guild quests will depend on invasion system as spoke earlier (f.e. only lvl50 or lvl10,20,30 etc).

Also i'd upgrade reward system, cause hmm...
Lvl 10,20,30,40,50 invasions would be quite impossible or rly hard to finish for low lvl guilds with not many high lvl players. Now I realized that invasion for average lvl of guildies would be better, so guild can accomplish invasion and guild leader can get reward. Also this wouldnt be that easy for high lvl guild with 50lvl players, like only 1 wave of 50lvl mobs , would be far too easy.

Out of event:
This just came up but maybe there should be NPC in every guild town with some special items so every member could exchange some fame points for those items just like couple shop in aven, or much fame points for smth rly good.

I did play a MMO with a similar invasion thing, but they handled it MUCH differently.

1) All the invasions were simultaneous, and anyone could fight in any town
2) The monsters appeared in the rear of the town, so they wouldn't block the entrance/markets from people who didn't/couldn't fight the current mobs.
3) Although the monsters did drop items, the main reward was to the first 3 guilds to clear the monsters from their towns...