No matter how much I train I just cannot afford the items to beat the challengers for this event.
DX I need to spend some more time training but I keep forgetting.
I fail lol.
Did you look at the Battle Chat? I created a board there that lists out really cheap weapons that work, not to mention several battlers (coughs myself included), are giving out Rainbow Star Rods to help.

you don't need to spend a lot on weapons to beat them. I didn't. I didn't even use really powerful weapons.....
I didn't think to ask tbh. I've been grinding away trying to do it myself. I have a few weapons for the lava weakness guy (saw that in your guide I believe).
I think my battle technique sucks then XD I'll keep trying. Can't say I'm not determined.
Well, if you want to do it yourself, the prices are going to tank on most of those weapons soon, as everybody beats the opponents and tries to sell their weapons all at once. The Rainbow Star Rod is dropping rapidly, for example.

Oh! Thanks for telling me that. I'll remember to make a list of the weapons I want to use, or that are good to use and I'll check their market rate.
That makes me a little more hopeful XD
My weapons were super cheap. I'd suggest giving these a shot: and a healer like

The Grimfruit is insanely inflated right now. I would say a is a little better right now.
Of course, with the easy plot opponents, all you need is a Rainbow Star Rod for healing.

Ah, well I haven't checked the prices on the fruit since it was in my armory before the plot started. 8D Guess that would have been helpful. XD

I'm sorry to hear that! I remember my build being posted on the first page of the 2012 Plot Discussion; it's really easy, cheap, and involves no expensive weapons! (Plus I used my untrained pets, so you don't even have to worry about training.)
The potions are mighty inflated now, but you can RS them at the Apocalyptic Apothecary (get Light, Magma, and Water.) The Item Hunters Wand is cheap-ish, and the Mace of the Red Rreign is really good to save for (as it has wind affinity already, and is a good healer.)
Fuego is weak to water, Escharcha to magma, Shadow to light, and Stone Hombre to wind. 8D