The past tense of come down on like a ton of bricks is came down on like a ton of bricks.
The third-person singular simple present indicative form of come down on like a ton of bricks is comes down on like a ton of bricks.
The present participle of come down on like a ton of bricks is coming down on like a ton of bricks.
The past participle of come down on like a ton of bricks is come down on like a ton of bricks.