I play videogames. I also Play magic the gathering and Dungeons and dragons and people say that this is part of being a bad christian. I belive that that isn't true. It apperently has to do with "spellcasting" and "magic is evil" but the chronicles of Narnia is supposed okay to watch and it is filled with magic. I also along with my youth pastor Play Diablo 3 which you in fact Kill Diablo which Means Devil. so Is that sac religious? because I don't see a problem with it.
I think there are far worse things one can do as a Christian than that.
BUT, it depends on your priorities:
Do you spend a lot of your time on theese things?
Would you rather play Diablo than read the bible / go to chuech / pray etc ?
Does it agitate you/ draw you into the game?
If so, it is indeed bad for you.
As for "making you a bad Christian", we all are bad by Gods standards, the secret is to realize when you do wrong, stop doing what is wrong, and then not let the devil tell you any lies about you not being worthy. Jesus came for the sinners, not the "perfect",
Keep in mind:
Whatsoever things are true,
whatsoever things are honest,
whatsoever things are just,
whatsoever things are pure,
whatsoever things are lovely,
whatsoever things are of good report;
if there be any virtue, and if there be any praise, think on these things.