Indiana Code Title 34. Civil Law and Procedure § 34-6-2.1-174

(1) any action in which the validity, location, wisdom, feasibility, extent, or character of construction, financing, or leasing of a public improvement by a municipal corporation is questioned directly or indirectly, including but not limited to suits for declaratory judgments or injunctions to declare invalid or to enjoin the construction, financing, or leasing;  and

(2) any action to declare invalid or enjoin the creation, organization, or formation of any municipal corporation.