No option to play as a human hunter with a 'pet' monster which they're forcing to fight in battles, forage for food and eat rare candies to help them evolve in a direction that would be beneficial for the hunter? It would help with the roleplaying if the rival humans could trade smack talk before getting their giant beast to battle each other for supremacy. Defeating an Apex predator would give you the option to try and tame it, using it as one of your pets until it dies in bloody battle for your glory. A bit like in [i]Pokemon[/i].

Then again, you could take the RP in a totally different direction and make it a little like [i]Horizon: Zero Dawn[/i], where the monsters are machines which the humans can hack and take control of. By destroying other monster machines the hunters would be able to salvage parts from them to upgrade their favourite pets. Defeating an Apex predator would let you salvage some of the advanced tech from its body and bolt it onto your own monster, but if you get defeated in battle an opponent might rip the shiny tech off and start using it themselves.

And another different direction would be to have the monsters similar to the Zerg from [i]Starcraft[/i], the Kaiju from [i]Pacific Rim[/i] or the Tyrandis from [i]Warhammer 40k[/i], where each 'hive' is controlled by a central intelligence which can spawn creatures with different abilities depending on what they need them to do. Players could take on the role of one the the 'overminds' breeding new species in competition with the overs, trying to gather new genetic materials to unlock new traits, abilities and skills, as well as biological material to actually grow the beasts. Defeating one of the Apex predators would then give you the ability to spawn a clone of them, but you'd have to collect enough biomass to feed into the spawning pool before being able to make something that big.