Good idea, horrible execution. In L4D you could actually do SOMETHING before getting killed, this gives you really nothing to do whatsoever. I've played as a shovel weilding graveyard zombie, a shrieker, bloodshot, an arm-blade boat J'avo, and a showy mountain crow creature, all of them went horribly.
When i was the zombie, all i could do was trail the path untill leon and helena finally stopped for a second, only to turn around and kill me in one hit, it was a 5 minute chase for nothing. I later got to play as a shrieker and a bloodshot when leon and helena were trying to enter the cathedral, but that really sucked. All i got to do as a bloodshot was struggle getting out of the grave and over the fence, getting shot and dying when i landed, and as a shrieker do the same thing, except charge up my shreik first, never getting to actually use it.
When i was a boat J'avo, I noticed that all of their attacks take like 5 seconds of standing there charging up before they do anything. I jumped of a ledge behind chris, and pressed the slash button, but my guy reeled back and charged up for 5 seconds. Chris just casually hit me once to break the stance, and i was incapacitated from there, helples while he pummbled me. I spawned again, but it took me like a half a minute just to crawl out of a hole, and by that time chris and peirs were running faster than my character could follow so they made it to the end without me even seeing them again.
The crow was the most useful of them, but that doesn't say much. When flying around, you can't controll your altitude, it's like you're not flying at all, but hovering two feet above the ground. Since you can't see anything in the snowstorm, i would spend 10 minutes following the enemy marker, thinking i was gaining on them only to find out that i had been flying into a wall. Other times i actually saw that i was getting closer to the marker, only to find out that there was an invisabe wall seperating me from Jake, or that they were one story above me, and that i had to double-back across the map and take a different route to get to them. The actual attacking part was the worst. The crow stops for like 10 minutes in air before swooping down, and he was long gone by then. It got to the point where i had to plan where he was going to be 10 minutes from now, and swoop towards there, only to misproject by an inch and have to do it over again. Sometimes for no reason at all, I'd be facing and aiming at jake, when i pressed swoop, and then randomly the crow would choose a whole different random direction to face, like off to the right somewhere, and swoop out towards the middle of nowhere. Sometimes i would grab Sherry, which was also frusterating because the AI does not take damage, so that was like a wasted attack, sherry was like a meat-shield for jake.