In
the super-late game it doesn’t really matter if you have 35 or 20 health. The
damage you receive becomes bigger and bigger, so two or three big losses will
likely eliminate you in either case. This means the optimal strategy is to get
the most gold possible even if you’re hanging by the skin of your teeth and
then to all-in on your army in the last possible moment. Spending gold early to have a
bit more HP than your opponents is a bad strategy in most cases. It will buy
you one more round at the most while having a stronger army (due to spending more gold in total) could keep you in the game for much longer.