https://www.youtube.com/watch?v=lOcD2iEcsck
Is this how you train to survive overwhelming odds?

Let's see what all these clips have in common:
1) AGGRESSION.
This is the most important thing.
None of these men just accepted being the victim.
2)NO QUESTIONS ASKED.
When things have 'crossed the line',
hit anyone that comes near you.
Don't allow anyone to grab you.
3)STAY AWARE.
You cannot fixate on any one or two individuals for long;
your rear and flanks are most vulnerable.
4)MOVE.
You may be cornered and not have the option to move,
or have a strategic position above the attackers, or be in a doorway/narrow space, etc. which allows you to only fight one at a time- but in open space, keeping moving is vital.
Tripping over things, though (or going to the ground for any reason), has to be avoided at all costs.
5)LOWER THE ODDS.
Fighting one person at a time can be hard enough;
fighting more than one is a very hard task.
If you can manoeuvre yourself and/or them, so as to fight one at a time (particularly if you can get the first shot/s in on each person), it will increase your odds of going home that night
(and not to the hospital or the morgue).
6)USE AN EQUALISER
A weapon can mean you can either hurt them quicker,
keep them physically at bay or psychologically deter them and perhaps weaken their resolve.

There may well be more points to consider,
but those are the ones I've learnt from the situations I've been involved in, seen (both up close or in footage), and from the advice and insights of experienced fighters and security professionals.

Stay safe and good luck!