The best way I've found to get through this game is to do the following
1) Breed with the Demonic beasts until somewhere around the 25th - 30th birth. The trick is to use selective breeding by breeding with one around three times and then begin breeding with the one with higher stats. Your womb gets stronger with every birth so the child you give birth to will progressively be stronger, but this is also paired with the father. The higher your womb births + the father's stats and skills will make stronger children.
2) By this point you should have a strong enough Demonic Beast to go aaaaaaall the way to the left side of the map and kill the tentacle beasts. Before that, get the map from the Demonic Beast shopkeeper. This will help with Fast Travel and can keep you from getting lost if you start to wander between zones. Don't worry about the other creatures yet, we'll get to them.
3) Subjugate tentacle beast lair. The battle shouldn't be too hard if you have a Demonic Beast with earthquake and other strong earth skills. The game doesn't give a straight informative session on stats and elemental resistances, and it doesn't really give you a clear sign of who is weak to what. you have to use your judgement based on damage numbers and logic (don't take tentacles to fight slugs because lol water damage).
4) With the tentacle beasts subjugated, time to SMASH (the good kind) with them and get some kids. Thankfully the demonic beasts should have plenty of children to keep living for a while so you can ignore them till later. I would say around the 15th -20th kid you should be good to defeat the goblins. Time to use that handy dandy map and teleport to the Beast Lair. Go right and then work your way North East. The Goblins should be easy to find. Defeat them and begin to SMASH!
5) Repeat step 4 with the goblins and then off to the fairies. Surprise that little tree huggers are weak to fire eh?
6) Check on the demonic beasts life span and see how much longer they have. As far as I know the lifespan of the creatures is slower if you haven't subjugated them yet. I could be wrong on this but I haven't tested it to be sure.
7) If they are slower or the same speed, the Orc and Minotaur will start getting low so we should move.
8) Slugs are next though as they give good skills to you with their births.
9) Have you been checking the shops? They can give good rewards and fast breeding for more kids although you won't be able to use the selective breeding trick since it's only with the shopkeeper. Keep that in mind and grab the unique items while avoiding the seeds.
10) Whatever your strongest bond is, take them to the orcs and subjugate them. The map should help with their location.
11) Optional: Breed with the Orcs so the Minotaur gets to be defeated by his rival
12) Take your strongest Bond to beat the Minotaur (praying the old fart is still alive. He was for me). His location is past the fairies and through a cave.
13) Subjugate the Minotaur and you now have every creature on the island subjugated. Hooray! Now it's time for endgame. Use the shop trick for quick child making on any creatures that are low (like the beasts) and then start selective breeding your favorite creature to get access to the temples, defeat the guardians, and get whatever ending you wish.
That's the very quick guide to get through this game. Albeit, it's a long and tedious drawl to get through as you'll be seeing the same scenes over and over again (holding ctrl is your best friend) to get enough births, skills, and strong enough bonds to get through. Thankfully, birthing cycles become shorter due to the strength of your womb catching up.
I don't know how I got the extra items like the multicolored stones (one I literally got from random thanks to having a tentacle beast walk past a certain point but I assume that's if you have a male with you (WHICH YOU SHOULD AT ALL TIMES)). So if anyone wants to add how to get all the specific endings, stones, etc please do.