I've read how his powers work. I've read several build/strategy guides. I still don't get it.
It seems his 1st ability is universally regarded as rubbish, which I can agree with. It's an elemental breath weapon, like a dragon. Awesome right? Not so much. When a dragon uncorks its gastro-destructive belch whole villages cease to exist. When Chroma does it, it's like trying to beat someone back with a garden hose that you're holding your thumb over the end so it comes out as a mist.
Most builds focus on his two and three, being Elemental Ward and Vex Armor. Supposedly you activate both these abilities and with the right build, Chroma is a super tank. But... The duration is pretty damn short, even with a max Continuity, far too short to be truly useful. Also, it's an armor/vitality build, and I don't have life strike or any other means of regenerating my own health. Given that, Vex Armor is nigh useless and Elemental Ward is best used as a brief get out of trouble power.
This brings us to Effigy, his ultimate. Chroma throws off his pelt and it acts as a sentry, dealing elemental damage to any who get close. This power is modestly effective at lower levels, with the added benefit that enemies killed by it have a chance to drop increased credits. Cool. Unfortunately it doesn't do enough damage to be good at killing things, it drains power faster than Diddums can suck down a beer, and mods that increase power range have NO effect.
If one of you all figure him out, get back to me.