In comparison to other tanks of the era, the Char B1 was quite heavily armed, packing a 75mm Howitzer intended for use against fortresses and bunkers.
The tank was designed as a breakthrough tank, although it could never shine in this particular role, as war rather came to it than vice versa.
Despite beeing a relativly heavy and hardly manouverable tank, it still had proven to be a substantial speed bump for the Blitzkrieg. As such you may hear stories as that of the "Beast of Stonne"; a lone char B1, that eliminated an entire Armored Detachment on its own.