Winter Reindeer: how to get the pet in WoW Forever
Winter Reindeer is a companion pet from Classic that returns in World of Warcraft: Forever. You learn it from 
Jingling Bell.
In short
| Item | Jingling Bell |
| Source | Drop: Archibald |
| Where | Undercity |
| New in Forever | no, from Classic |
| Account-wide | yes, according to Wowhead |
How to get it
It drops from Archibald in Undercity.
What changed since Classic
The item now teaches the pet: it becomes a spell and no longer takes a spot in your bags.
Wowhead’s database marks the pet as account-wide: learned once, it would be there for every character. Blizzard has not confirmed that itself.
More pets in Undercity
Every pet of WoW Forever, with where it comes from, is in the pet guide.
Frequently asked questions
How do you get Winter Reindeer in WoW Forever?
It drops from Archibald in Undercity.
Is Winter Reindeer new in WoW Forever?
No. Winter Reindeer was already in Classic and returns in WoW Forever.
Sources: Wowhead