Tips:
1. Wealth and multi shot are one of the best upgrades at the beginning.
2. You can right-click on upgrade to block from restocking
3. At the beginning, it is best to spend stars on manifest (multishot upgrade)
4. Only then "bellow" to the 3rd level
5. And then "peer" to level 3 (this makes you practically immortal, you no longer need to use Heal)