Striving to become more heavy seems like a foolish pursuit.
For example, with travel, insanely lightweight is supreme. Any additional weight you add is positively detrimental to you.
Also with cars, making a car heavier, even if you add more horsepower is bad. Why? The rules of physics. A car that is heavier, irregardless of how low it is to the floor or wide, will perform less well at the race track. This is typically why very lightweight cars are more fun to drive, let’s say a Mazda Miata, or a mini Cooper.
In terms of weightlifting, bodybuilding in the gym, do not strive to become heavier. Typically when guys do this, they just end up getting fatter.
The simple approach then is just lift insanely heavy at the gym, eat a lot of meat, no starches no carbs no vegetables and fruit etc. Just eat until you’re naturally full, and then let the muscular gains come to you naturally.