Palworld

Lily and Lyleen can be found in a tower to the north in a cold district. You will need some armour that resists the cold while traveling there. It is a grass based boss fight so bring some fire types with you. You'll need to take down just under 70,000 HP in 10 minutes to win.

Check the video below for an exact location of the tower on the map:

Lily & Lyleen
Location: Free Pal Alliance Tower
Challenge requirement: 69K damage in ten minutes
Tower of the Free Pal (185, 28) Lily and Lyleen
Lyleen is a Grass-type Pal, so make sure to populate your team with your strongest Fire-type Pals before you take it on. We particularly recommend Vanwyrm for this fight since you can ride it to gain better maneuverability and direct its attacks manually while using it as a mount. However, this does mean that Lily & Lyleen won’t split their attention between you and your Pal, so be sure to remain on the defensive as much as possible if using this tactic.

Lyleen can emit a poison cloud directly ahead of her, so remain at a distance and aim for Lyleen’s head for critical hits. Avoid its homing bubbles and hurricanes at long range, as well as the seed grenades it periodically scatters across the battlefield. It also fires off a swift three-shot missile that you can avoid with a well-timed dodge or ducking behind a pillar.
information is from onine web articles but helps alot

This is a general comment about the game in general...

Try to get Daedream (#19) and Dazzi (#63) as soon as possible. If you craft their collars, they will both follow you around (together) and act as support. DON'T make them active. They don't take damage like your active pal, and they can do SERIOUS damage. Against all of the bosses, I've lost all of my active pals, but they've continued to wail away. I wouldn't have beaten Shadowbeak without them, even at level 50 with an overpowered handgun and a level 50 dragon team. They also knock down every pal you run across if you need them to.

So yeah. Daedream and Dazzi. Make them a priority. Trust me on this.