UPDATED: Team Fortress 2 Engineer Updates Day 4 – Now LIVE

As some of you might be noticing right now, the Engineer Update is going to go live soon.

Valve has released 100 ultra-rare golden wrenches for the crafters of Team Fortress 2. Everytime 25 has been found, new details of the engineer update will be released.

Day One of the much anticipated Engineer update brings two things on the table:

The Golden Wrench – You’ll see when you use it. =D
The Frontier Justice – A special shotgun that is designed to be used in conjunction with the sentry.

Day 2:

The Wrangler – This nifty item allows you to manually aim your own sentry. Very powerful gizmo that gives a 66% damage shield and increases the firing rate of the sentry.

Day 3

New Map: Hightower – A new payload map

Day 4

Update is now live. New weapons include:

The Gunslinger – Allows a third critical hit on the third attack when melee. Is required for building the mini-sentry.
Mini-sentry – cannot be upgraded or repaired but can be built 4 times faster than a normal sentry.

Source:
TF2 Blog