The enhanced permeability and retention (EPR) effect is an attractive avenue to target tumors: The size of the drug is the key to accumulating predominantly in tumors. Therefore, to increase the molecular weight of arene ruthenium metallaassemblies, several strategies can be adopted, and we present here our first step in the design of larger and heavier discrete arene ruthenium metallaassemblies to reach an EPR-size dimension.