More of a hazard than a help for sure. Contamination with Zombie makes it useful, and Global Cooling if you can still do something like attach nails to your boots to make yourself unable to slip in the final release would have quite a bit of use. However, Ignition is just bad. To really make good use of these, you need all the surfaces created to harm enemies and either help or not directly impact all allies, which makes them difficult to use.
Personly I think that Ignition and Global Cooling were made just to counter Zombie+Contamination combo.
Perhaps, but I stand by my assessment that you need to really be sure that it'll do more harm to your enemies than to you if you're going to use them, and these are the ways I can see. I mean, unless you can get fire resistance to or above 100%, Ignition creating massive fire surfaces is likely to be just as big a problem for you as your enemies.
