I'm thinking of securing my job the way I think is easiest for me.
How did you secure your job?
There is one colleague at work that has been there for ages that I'd like to get rid of. I'm going to blame him for something he didn't do to get him fired.
You tend to want more job satisfaction, but to make this happen you think you have to have a colleague lose their job which is malicious. They need their job just as you do, and if you get rid of them then they may end up homeless. Be more of an outstanding worker and guarantee your success in an honest way.
Those words are of no use to me. I am going to get rid of him regardless.
Your motivations to get rid of him are selfish and that leads to bad outcomes for everyone involved. Think about the good of your co-worker and the good of your company instead of your own personal ambitions.