Any woodworking chisel will work for ice sculpting, but few woodworking chisels are ideal for ice. Because ice is grainless and soft, a very acute grind will work with ice. The shaft of the chisel doesn't need to be rigid. The blade won't dull as quickly, and the wood grain won't cause the blade to "wander," affecting the stroke of the chisel. Specialty ice carving chisels and chisel sets are available, and most are long-handled. Blades tend to be wider, with 2 inch being common. And chisel shapes tend to be simpler than woodcarving chisels: Simple straight chisels, "V-knives" and basic gauges or "spoons" with "U-shaped" blades.
Mallets, as with wood and stone sculpture, work great in conjunction with carving chisels. They aren't necessary with ice as arm-strength is plenty to push a sharp chisel through the material. But, mallets provide controlled, short bursts with little risk of taking off too much or breaking the ice with a long thrust.
Chainsaws are great ice sculpting tools, especially in the first, rougher stages of the sculpture. As with other chainsaw sculptures, the shape of the chainsaw bar is important. It's best to have one that is is very short from top to bottom. This lets you turn the saw in a tighter radius as you're cutting. Electric chainsaws are most common, and necessary for indoor applications. Small to intermediate-sized gas saws are used outdoors.
Several grinders are well-suited for ice sculpting. Angle grinders, die grinders and angle sanders are all great tools. The surface area of the grinding area dictates whether it's a good detail tool or better used for removing a lot of material. Electric grinders and sanders are used. If the motors are not sealed, though, pneumatic tools can be a better choice in a wet environment.