Which one should I keep and which should I forget, Fang could badly poison and tail has higher critical hit ratio.
Poison Fang has a 30% chance of Badly Poison the target,
Poison Tail has a 10% chance of Poisoning the target and has a High Critical hit ratio.
If you ask me I would use Poison Tail since it has more special effects
So Poison Tail it is
I would go for poison tail because it has a chance for a high-critical hit or poison and overall it has 40% took off 100% which leads to only 60% of poison tail doing anything extra while as poison fang has 70% of of it doing absolutely nothing extra. ^.^