What a cool plant! Bet it's a little stinky, judging by the flies on it.
The popular name for it is "carrion flower." That gives you a true idea of its scent!
How often are you watering yours?
I water it very infrequently as I do my other cacti and succulents. Maybe every 10 days to two weeks.
Mine is tiny, the arms are only about 1/4" across and at one point it was all slumped over, so I gave it a drink. It's in the cactus mix from Cactus King where I bought it and it's getting quite a bit of full sun, but it doesn't look too happy.
Mine lives in partial shade and has been happy there, so you might try that. I find that it doesn't require much water at all, but then it is not in cactus mix. It is just regular soil-less potting mix. It has been left outside in the last two winters - since it has gotten rather large - and parts have been frostbitten and died back but it always regenerates quickly in the spring. They are tough plants. I hope yours perks up.
Me too! Happy birthday!
Thank you! It is.