Originally Posted by
Cobblemaniac
Do what you can. Go as high difficulty as possible, but where you can clear it. This is the general rule for advent events.
For your future reference, below contains advice for general content (non event) and 2 other events.
First, raid events, possibly the easiest one for you... if you have enough seeds on hand (recommended 200+). Jump into any public raid, get a couple of hits in and grab the rewards. Even when you hit once, you'll still get the full rewards (outside of MVP and sub-MVP). The only thing to watch out for is... don't be a dick and enter ragna raids with 19/20 ppl and still more than half HP, or something similar.
Union events are... well I hope you find a good union, that is all that makes the difference in your getting all the rewards in the event (plus a good ranking, therefore more rewards). Well, that and your individual PP, but that improves as your setup improves. The only thing you need to optimise is really measuring the AP to grail ratio. Currently it's more worth to solo Standard Lilims, and more worth to assist Expert Lilims. Always join a Lilim raid hosted by your union member.
Annnnnnd general. Rule of thumb for farming elemental materials is go ultimate. The lowest drop rate of gold chests (tier 3+ materials) in there is 2, compared to a whopping 0 in expert. Due to the possibility of getting cucked by RNG, my recommendation is run the level that guarantees you get stuff at least.
Accessories are straightforward. Farm the highest tier you can manage.
Raid disasters/ catastrophes are an interesting case. My recommendation for levels below ragnarok at the moment is to solo standard before farming expert, considering the platinum chests they drop don't differ by a lot. Then, touch ragnarok when you're able to do at least a decent amount of damage before dying (being able to stay alive while the boss is below 75% HP is a good starting point), and at this point solo is probably out of question until you get a better setup. As for joining these raids, ragna obviously gives you the best stuff, but stick to the rules of not being a dick. ESPECIALLY for water ragna. If you wanna know why, check out the elemental catastrophia info dump thread... or you can ask for an explanation here.