Attach a shield bubble mesh to the player which dies after 5 secs..
Health bubble maybe that also dies..
Can't get any more imaginative right now :/
Spawn protection
Re: Spawn protection
You might wanna have a look at the code of the shields in Galactic Conquest. These can be dropped (like C4 or mines) and create a half circle "energy field" that doesn't let bullets pass and still can be walked through, hurting the soldier a little bit. Some kind of obstacle object, like barb wire, but with the ability to stop projectiles (and only these).

Re: Spawn protection
Spawn protection is hard to deal with. I guess just spawn the people in a floating building object or floating landmass object and have the players jump out of the object. The building or landmass could act as a "physical" barrier.
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