My Doom Drake is currently on the 12th level of the Tundra. How many levels are there? I also haven't come across anything too spectacular like a Lykos Egg or anything. I've been searching through and even waiting days for the Drake to be able to beat one monster but I just keep finding the green portals. Is there something I'm missing? I have yet to find a Pristine Snowflake either.

I don't know if there even is a limit to the levels. I'd guess as long as your pet can handle them, the game can make the mobs harder :p

The Pristine Snowflake is supposed to be very rare, so it's no wonder you haven't found it yet. And Lykos eggs are also not that abundant. I just use multiple pets to explore as far as they can. If you're mainly looking for Lykos for example, it's enough to only do the lower levels, so even weaker pets can do those, since the eggs can spawn on lower levels as well.

I know a person who went to lev 17.

I personally cant manage to get further than lev13.

But since I have only one pet that is good enough to go at least 10 levels I decided not to wait days for defeating one guardian. I just went multiple times to levels 11-13 and finally got my pristine snowflake. But it took me almost a month and I used many energy drinks to make my pet be able to enter tundra more often.

I think that you virtually could go endless, just at some point guardians are becoming so hard that it is impossible even with the best of best pets to go further...