Corow Showdown can be farmed on Hard or Very Hard fairly easily for newer players, allowing them to easily accumulate event items. For newer Light players, unless you happened to draw a good Light ATK summon, getting a copy of Corow to use as your main summon can be beneficial.
None of the event weapons are worth spending resources on, so you can use them if you happen to get them, but don't use items to buy them or spend fodder skilling them up. As with all showdowns, you can buy 5 Half Elixirs per month and you should be able to get enough materials to buy all 5 each month while using less than 375 AP, so it's worth spending the time to farm materials.
Simplified drop table
Disclaimer This section is still being written; it may be wildly inaccurate or missing significant data. If you can help please feel free to edit it but please write edit summaries, preferably with sources.
Gain DMG CutTaking less DMG Damage Cut reducing damage taken for all elements. Warning! Does not work for Plain Damage!.
Stomp
Light damage to all allies and inflict ?Verification needed. .
Boss
Corow
75
11,000,000
◇◇◇
Yes
Special Attacks
Triggers and Notes
Toroidal Plasma
Gamma BlastN
Light damage to all allies. Inflict ATK DownATK is lowered and -10% charge bar cut.
FraunhoferOD
3-hit Light damage to random allies. Last hit inflicts ParalysisCan't attack .
AlfvenTR
Massive Light damage to all allies, removes all buffs, and inflicts BlindedAttacks have a slight chance to miss . Corow gains Water DEF DownDEF is lowered for water DMG .