I hope this is the right forum to ask this and if its not please forgive me but....
Ok im making a single player campaign (for the first time) and some of the ideas is i was wanting the main character (a CIV) to like "evolve" into a high temp. and i was wanting him to be able to shoot scarabs from around him. Is there a way to do a trigger to create scarabs at a location?
No, Scarabs cannot be created, you will need a spare space on the map for a couple Reavers loaded with Scrarabs, have a unit for a different player beside the reavers for them to attack, and when the scarabs are needed just teleport them to their destination! pretty simple

You will also have to run Junkyard dog on the scarabs or they will fly to the top left corner of the map.
Eh, I guess ill have to just think of something different cus i was wanting the effect of like these energy attacks coming from the main character, not him creating units to attack. Thanks alot for your responses tho.

Try using the scarab idea, it'll look pretty good. There's no way to have like "energy beams" shoot out of your character besides unit death animations and observer arcs.
You can use a observer and move it making other observers blow up making a cool effect but it would be a bit slow.

You could always teleport scarabs.
If you teleported like 6 scarabs at a time to the units location it could look pretty cool and with junk yard dog they would attack stuff.
O and make sure the unit the reavers are attacking has a decent amuont of health so it will survive while the unit is not using scarabs. Or you could just constantlly set it to full health.