Xenogears Crossover Event

[Absimiliard]

This is the sort of thing a lot of the older JRPG fans would dig. They could pull in Fei, Elly, and Citan (or Bart) for it. Maybe even have Id or Kahran Ramsus make an appearance as the final boss of the event.

A scaled down version of Yggdrasil, Weltall, or Welltall-Id would make the perfect mount reward. The lattermost of these could even be made relatively cheaply by using Cruise Chaser's skeleton and some of its animations. Overall, Weltall-Id is probably the one a majority would prefer. Heck, given the Yggdrasil's design, they could probably modify the whale (or Lunar Whale) into a miniaturized version of it. They could put the mount up on the online store after the event ends for a fairly substantial profit given how epic any of the options would look - though again, Weltall-Id would be the smartest option.