[Shangrila00]

Check the booster guide on the wiki. I think it's pretty complete, with the exception of the EDM additions in CBM. Summon Treant can give you the N/W and N/E crosspaths starting with just N, Great Krakens can give you W/B and a chance at E/N also, both of these in Enchantment. Asynja and Ember Lords can also get you crosspaths, but at Conjuration 8 and 9, you might has well get Tartarians for all your diversity needs.

On Eriu, you have 2 heroes with death. Unfortunately you have a ton of heros including a multi-hero, so even at luck 3, you might never get them in good time. If you do have the good luck to get those heroes though, you can use spectres to get astral and the E/D crosspath, then use the E/D crosspath to cast Hidden in Sand for all your fire/death/astral needs. Sadly, you can't get S3 with this, so no astral rings unless you get artifacts, which isn't going to happen with your craptastic research.