QUOTE(Vilis @ Aug 25 2018, 09:56)

I have some questions on Monster Lab. My goal is to get lots of gifts (duh).
1) What's the best way to spend Chaos Tokens? Should I just keep getting new monsters, or is the Scavenging upgrade worth it too?
2) What's a good level to upgrade my weakest monsters to?
3) Is there a good reason to upgrade a monster to the maximum level?
1) More and more slots. You can start spending
one token per monster in Scavenger past 50 monsters or so. And then probably the second Scavenger upgrade past 70 monsters or so. I haven't made the exact calculation, but it shouldn't be far off.
2) Keep feeding their morale up with crystals until you can't do it anymore or you consider it becomes too expensive. Just make it so you don't waste morale when upgrading them and you should be fine. That much should make you save
a lot of Happy Pills which will be useful once they start costing an arm and a leg. IMHO, you shouldn't be having much trouble till you go beyond 10 primary upgrades and 20 elemental upgrades. It takes a monster many months to reach that point by "crawling" the PL that way, but it pays off in the long run.
3) If you don't include bragging rights and pride in the valid reasons, the answer is a big fat no.