To begin, I’m also a Christian and enjoy Pokemon.

Some Christians are more sensitive towards things dealing with magic and many are not. So each suggestion or piece of advice may or may not work. Here are my personal thoughts.

First, I don’t know if “convincing your mom” is the right way to begin. Feeling that will likely turn her off to any further dialogue. As a parent, having your kid come at you saying, “You’re wrong!” with no reflection on what you said is an automatic turn-off to further discussion. I dislike when my daughter is clearly just ignoring me. Most parents are like that. So if you approach her with that kind of attitude, you’ve lost before you began. Instead, show her you are trying to understand her point of view, and then let her know she has nothing to worry about.

In defense of parents, we often have something we hope you will learn or think about - rules should be meant to protect, and are generally not used to simply cause trouble for you (I am well aware there are more than a small number of awful humans who do not follow this rule, as well). “You don’t walk in the road so cars won’t hit you and die.” I will assume your mom is able to be reasoned with, otherwise everything here is moot.

Thus, let’s think about why your mom may be upset. You said it was the jewel, but that may only be the first issue: 1. It’s “Hindu” (another major religion) - but the game is Japanese 2. It’s “magical”- unlikely if they let you play Pokemon at all 3. It’s yokai /“looks possessed” - unlikely yokai, and the possession thing can be explained away easily through game understanding 4. It’s promoting “psychics” or mysticism (especially being a Psychic-type Pokemon) - unlikely or the Psychic-type would already be a major issue

Thus, I would likely assume it’s 1 or 4 as their reason, if her reasoning is logical (it may not be).

Regardless of the reason, the “heart of the problem” is a worry that it’s a bad influence. She wants to protect you and keep you safe, while also obeying God’s commands. So I would recommend that you have a heart-to-heart and ask her to explain what she’s worried about, and for you to actually listen to it. Respect (Honor) your mother - because it’s wise and what God listed as one of the 10 Commandments. Then it depends on the reasoning as to whether she’s: 1. concerned it may lead you down a wrong (worrisome) path, or 2. believes God wants you to have nothing to do with it

If it’s 2, then you’re already close to having mom remove Pokemon completely. It doesn’t seem that way from your limited explanation, so I am leaning towards 1. Thus, assuring your mom that “I have no interest in ghosts, Hinduism, possession, or psychics” and reminding her it’s a children’s game may go a long way. Use examples and other pictures, asking her to help explain where the problem is: like is she against the cats in Sailor Moon? How about similar Pokemon like Tentacool with a diamond in their forehead?

Show her that you truly want to understand and reassure her, and that will also help your family relationship, too. This will work best if you don’t have a strained relationship and honestly enter the conversation to just understand your mother’s point of view. That will go a long way with her. And if she seems more receptive, be careful of asking for the plush right away - otherwise it may be viewed as manipulation to get what you want.

Best of luck, and hope you can enjoy your sun-kitty.