I've been using Fire and Ice Dual Blade which has blast damage. How does the build up for blast happen? If attack halfway, then let just says I decided to sharpen my weapon and didn't attack for a while, then if I attack again, would the blast build up continue from the point before I sharpen weapon or does the blast build up start all over again.

There are times where the blast build up feels inconsistent in my play through. Does monsters build up resistance and immune towards blast once the status been inflicted?

Blast Is just a status effect like any other in the game. Depending on the monsters strength(or weakness to it) determines how much build up you need for the first effect to go off. After the first, the second one takes more and so on. Some monsters are probably immune but most definitely aren’t.

You only afflict status on either every third strike or randomly 1/3. Don’t remember if it’s set or random but it is 1/3. Less so with those dual blades cause technically only one half of your weapon does it. You don’t have to worry about sharpening or time away from the monster, it’ll continue to build up and eventually explode but something like blast is really neat for low rank but less so the farther in you are because the damage scales poorly.

@vortextk:

So monster build resistance when first status happen on them.When I fought Behemoth I manage to creste blast on him 4-5 times in the first stage but as the we progress to next stage of the fight, the amount of blast I put on him become less.

Just to clarify, so for every 3 attack I did, I have 1 attack that will build up the blast attack or cause the blast itself?

Every 1/3 does build up, not actual effect. Actual effect is some math equation based on resistances, your gear, how many times this monster has been affected by that status etc. The mantle that increases status effect build up makes you cause build up every attack while that is equipped.

And yes that bit of behemoth makes sense. I don’t specifically know if monsters become completely immune or not to status effects but they become functionally immune at some point because they’ll just die before it happens again.