Requested by User:Jackythejack on discord
Chibi robo is 68 pixels tall, while the block is 149 pixels tall and wide. I'll assume it's also that long, making for a discrepancy overall of 2.19117647059 times
According the the game manual, Chibi Robo is 4 inches tall, 10.16 centimeters, making the block 22.2623529412 centimeters
22.2623529412 times 22.2623529412 times 22.2623529412 gets a volume of 11033.4972465 cubic centimeters. They can destroy up to eight of these so in total, it's 88267.977972 centimeters
This block is very clearly made out of stone, as it makes a pretty rocky noise when it explodes.
It appears to be fragmentation, so times 8 is....
706143.823776 Joules, 0.00016877242 Tons, Wall level