Well, relying on chemistry your creatures can play some ice/fire tricks.
Some chemical reactions need energy to occur, which results in cooling down the surrounding. If the body is able to produce these chemicals and keep them separate until needed, you could for example have a "frozen spit": a gush of saliva containing the chemicals is launched on the target, and once the chemical reaction freezes it, the target is trapped in a crust of ice. Maybe usefule for hunting small animals.
Some reactions produce a lot of energy. Again, if your creatures can isolate such chemicals and use them when needed, they could play "fire" tricks.
As real life example you can refer to the "bombardier beetle", which produces water peroxyde and Hydroquinone as defense mechanism
This reaction is very exothermic, and the released energy raises the temperature of the mixture to near 100 °C, vaporizing about a fifth of it.