Let me clarify what I mean by the above statement: There are multiple endings to this game and you don't have to complete the entire map to get to them. There are a number of endings in the game and thus far I have only found one of them. I'm not going to spoil things but the ending I have seen already wasn't terribly satisfying, so I am still searching around the map to see what I have missed.
Potential spoilers ahead
There are quite a few games out there with multiple endings but to my knowledge not many of them are metroidvania games. I don't know who did it first but Hollow Knight is a great example of how wonderful this can be. In Hollow Knight you can get to the first ending by completing a very small amount of the overall map and while it is still a bit tough, it is possible to get to the first ending without even powering up a great deal. Some insane speedrunners have found various glitches in the game in order to complete the first ending in under 10 minutes. The amount of dedication and memorization of the maps that these people have accomplished is some sort of Asperger syndrome something or other than I can't even comprehend.
Let's get back to Ender Lilies though.
After "completing" the game I thought to myself that there is no way that this is the real ending because in my search for tips on some really tough bosses - and the bosses are EXTREMELY tough in this game - I noticed that the tutorials involved skills or "spirits" that I had not yet obtained in game. Therefore, I knew that there must be a great amount of the game that I have not even seen yet.
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I've intentionally shown a very small portion of the map near the start of the game. The actual entire map is HUGE
One thing I really like about this game's map is the fact that once you have discovered all that there is to be found in a certain area, the map turns yellow to indicate that there is no reason for you to jump around looking for a hidden break in a wall. This was a real issue in Hollow Knight and other games because sometimes the place you hadn't found yet was extremely well hidden and the only way that a casual gamer like myself was ever going to 100% the game is if you had some online help.
Ender Lilies cuts out a lot of the this repetitive search by being very clear about what rooms you have completed. They also indicate certain exits or doors that you have no opened yet, which makes the going back with your new skills a lot easier and less of a chore. In Hollow Knight, I felt like a lot of the time I was just wandering over and over to the same places in vain with no real idea as to where I might even need to start looking next. I feel as though this little bit of help is a dramatic improvement that Ender Lilies made to the process.
There is a certain area that I at this point believe could be considered the "toughest" in the entire game called Verboten Domain and I only recently stumbled upon it after already discovering one of the endings.
A lot of this zone has some sort of poison mist that you can not avoid being damaged by. Therefore, tooling around in one area for too long is going to certainly kill you. This brings about something else about this game that I really feel like they actually did better than most if not all Metroidvania games that exist: There is a leveling system built in by XP acquisition.
If you are having a tough time with a boss or wander into an overpowered area, you can go and explore elsewhere and gain some levels. There are 100 levels in total and as you would expect, you are significantly more capable of dealing out and taking damage at a higher level. When I return to the beginning rooms at this point in my gaming journey, I one-shot basically all enemies. This an also be a lot of fun if you missed a boss or mini-boss in your previous exploration because you just kick the hell out of them pretty effortlessly.
This miniboss kicked the crap out of me when I was level 35 or so and I walked away from it out of frustration. I later returned at around level 80 and it was the opposite story. I didn't really even try to have a strategy and easily vanquished him.
I remain steadfast in my opinion of this game in saying that it is one of the best games I have played in years and if you are a metroidvania fan, this is a very good choice for what to play next.