Day 117, 12:00, for 8 hours: 211 zombies at ×25 health and ×28 attack.
Part of Endless tier 24, day 2 of 5.
When it ends: 
All-Purpose Strengthener
Fine Sheet Metal
Scrap Metal
Cold Cuts
Mystery Novel (Endless rewards, tiers 20-29)
Day 117, 12:00, for 8 hours: 211 zombies at ×25 health and ×28 attack.
Part of Endless tier 24, day 2 of 5.
When it ends: All-Purpose StrengthenerFine Sheet MetalScrap MetalCold CutsMystery Novel (Endless rewards, tiers 20-29)