Best quest

[Caustify]

For Sinow Spigells and Mericarols. Use to run MU3 for spigells, but I see those quests are gone now.

 

[Spuz]

For Sinow Spigells and Mericarols. Use to run MU3 for spigells, but I see those quests are gone now.

Spigell:

• [VR] Maximum Attack 4th Stage-C- CCA (14)
• [Episode 2] 7-4 end up at 2nd warp (4)

Mericarol:

• [Extermination] Phantasmal World #4 end up at 4F,6F (3,5)
• Maximum Attack 4th: Stage 2B. CCA only (6)

Taken from Monster Count Guide

The original post is old and needs updating as it doesn't feature any MAE/Custom quests and you can ignore any posts people have made featuring GuardianGirths Quests- (but it's a good guide to look at still)

Spoiler

for reference:
Villainous rift 1 and 2
Malicious uprising 1-5
Lost shock gungnir
Lost riot raygun
Lost devil sceptre
Lost chaos calibur
Lost heart breaker
lost son hopkins
lost master blaster