Unfortunately none of your Blade/Trap spells offer any additional chance for a critical hit. The gear you wear giving you Critical Hit is the only factor. You can also train in the Astral spell "Vengeance" for a 20% increased chance for 4 rounds.
It's important to remember that the amount of Critical Hit given in any piece of gear is NOT a percentage. If you access your wizard's statistics by pressing the "C" key and tab over to the section of Critical Hit/Block, and mouse over any one of the numbers under the different schools it will break down for you how much each piece is giving you and you can add all the percentages to get an estimated chance for a Critical Hit.
I'm slightly under 300 and it doesn't activate as much as I would like it to. I have seen those with over 400 and it's noticeably different, so perhaps that is the magic number we are all striving for.
I hope this helps you; good luck in and out of The Spiral.
I think their block critical levels must be very high. It does seem very rare for an attack critical to work in the higher worlds. On the plus side, I bet they don't critical on you much either. I know that is the case with my ice wiz. I am also happy about the critical heals I can cast, which still tend to work quite well.
I find this strange. Everytime I try and get a critical, it doesn't work. I have gear that gives me 146 critical.
I use a lot of blades and traps when I fight, I use Ice Giant spell. I am level 85 and I use only spells.
Shannon Duskgrove L85
Hmmm... based on that rating, you would have a critical rating around 25%, which means you should only get a critical about every 4 times. I can't tell you the exact number without knowing the gear you're using, but 25% is a decent estimate. Are you just not critting or are you being blocked? Also, pro tip: Don't worry about critical, it's really more of a PvP thing. In PvE, your critical has a tendency to either completely fail, be blocked, or just be unnecessary in street fights. Bosses usually block your critical anyway, so there's really no reason to worry about critical in PvE. Just go with damage, resist, and critical block and you'll do fine.