Basilisk Venom
Underwater is fickle, but I have no troubles beside that. The only times it doesn’t work is if the opponent has Aegis or the evade it. On pistol and short bow using auto-attack will waste the charges more often that not. When I ran a complete venom build (now I use 3 venoms and scorpion wire) turning off auto-attack is a must and learning to carefully plan shots with ranged is important.
Basilisk Venom in my opinion used to be much better off before they altered duration which it stays on charge, which was 45 seconds. This meant you could plan on using it whenever you needed it, but they changed it to 30 seconds on charge duration, which means if you spec 20% less cooldown, you still have to wait 6 seconds without it. So I preferred it the way it was before. But in my opinion, I still think Basilisk Venom is quite good though many disagree.
Thief – Radderic
Mesmer – Smash Kablooey