Glowing trail behind units.

I am making a capture the flag like map. When a person picks up the flag it appears over there head. The problem is it colorless, making it hard to tell which flag it is. I want to create an extra effect over the flag holding that help to identify the flag color. I was thinking it would be cool if it was like the pheonix fire effect and makes a glow tail or somesort of trail. I want 2 colors that are similar in style Red and Blue.

Does anyone have some suggestions of how to do this?

i have no idea how to do the glowing trail
but if you put the flag color and put it to 'player 1 - red' and 'player 2 - blue' and never change it, the flag's color should stay the same.

There aren't options to change the owner of the flag model once it is pickup cuz it is not a unit, its an attachment.

I've noticed that the Rejuvenation buff seems to leave a long color trail when in motion. Maybe you could crack open the .MPQ, reskin a couple rejuvenation models using the colors of your choice, then use it as a special effect in your map.

A trail can be left by casting locust swarm.

Create locusts with 0 speed, which are released after every long interval and make the spell duration really long. Have the locusts have negative hp regen, and spawn units upon death (these units have 0 movement, locust, and a graphic). So upon the guy getting the flag, give him this ability, let him cast it, and then remove it (I'm not sure if it can be removed and still work, but it should since it is non channeling).

So basically you leave a trail of units behind you.

You could use the absorb mana missile for the blue flag

You can download hero glows, just DL the 2 colors you want, then attach them overhead on the flag carrier.