I can’t really paint or play anything right now so just pondering game ideas and came up with this simple scenario. It has not been play tested and is just meant to give you some direction. I had Galactic Heros rules in mind but should be generic enough for any rules set.
Setting:
The distant planet (insert name) is home to the (insert name). A large and mostly docile animal that would rather flee when threaten, they will still put up a fierce fight when cornered [think like an elephant or rhino] or go into a rage if one of the heard is killed. What makes them interesting are the large crystalline growths protruding from their thick skin. The vegetation the (animal)s prefers to eat are saturated with these indigestible minerals. The minerals are excreted in special glands all over their backs but the process causes them to crystalize. These crystals are highly valued across the sector by the wealthy. Farming them is prohibited by the indigenous population which consider the (animals) to be sacred. Especially because the process of removing them cause the animals great harm and removing all of them will likely kill the creature.
Special Rules:
The (animal)s will try and flee directly away from any attacker but will attack any character in their path. Make their stats whatever you feel fits the setting but they should not be too hard to wound and have no more than 5. Attacks aren’t meant to kill the animals but to knock off a crystal. Every time it is loses a hit point it drops a crystal token on the spot which can be picked up in the normal way. Only 1 may be carried character though heroes may carry 2. When it runs out of wounds all the crystals have been removed, killing the beast. If one is killed the rest, if there are any, will become aggressive and attack the last character to injure it.
Setup:
for a 2 player game place 1 (animal) in the center of the table, for each additional player place another one within 6 inches of any other one on the table. There should always be one fewer on the table starting then number of players, this creates some competition. The players are groups hunting for the crystals to sell off world for a huge sum. Alternatively, 1 player may be a group that is indigenous to the planet who wish to protect the creatures by any means.
Winning: the group that has the most crystals off the table at the end of the game wins. For the indigenous group they count crystals still on the animals. Game length per player preference.
Photo for inspiration.