I'm so confused about counteracting in this edition. Maybe it's because I'm not an English native speaker, I don't know, but i cant' understand anything about it. :S
Counteracting:
Some effects try to counteract spells, afflictions, conditions, or other effects. Counteract checks compare the power of two forces and determine which defeats the other. Successfully counteracting an effect ends it unless noted otherwise.
When attempting a counteract check, add the relevant skill modifier or other appropriate modifier to your check against the target’s DC. If you’re counteracting an affliction, the DC is in the affliction’s stat block. If it’s a spell, use the caster’s DC. The GM can also calculate a DC based on the target effect’s level. For spells, the counteract check modifier is your spellcasting ability modifier plus your spellcasting proficiency bonus, plus any bonuses and penalties that specifically apply to counteract checks. What you can counteract depends on the check result and the target’s level. If an effect is a spell, its level is the counteract level. Otherwise, halve its level and round up to determine its counteract level. If an effect’s level is unclear and it came from a creature, halve and round up the creature’s level.
Critical Success Counteract the target if its counteract level is no more than 3 levels higher than your effect’s counteract level.
Success Counteract the target if its counteract level is no more than 1 level higher than your effect’s counteract level.
Failure Counteract the target if its counteract level is lower than your effect’s counteract level.
Critical Failure You fail to counteract the target.
So, here my doubts.
To be clearer le'ts say that there is "A" that wants to counteract an effect made by "B":1- What exactly should "A" roll to counteract an effect?
2- What is the DC of "B"?
3- How do I calculate the counteract levels of both, "A" and "B"?
Thx!
1 - Determine B's counteract level (typically spell level or 1/2 monster level or 1/2 item level)
2 - Determine B's counteract DC (typically spell DC or effect DC)
3 - Determine A's counteract check modifier (typically A's spell attack modifier)
4 - A now rolls a counteract check using A's counteract check modifier
5 - Result of check determines A's counteract level as per the given entries for critical success, success, failure and crit failure
Thx, so let's see the description of Blank Slate (rogue class feat level 16):
Your deceptions confound even the most powerful mortal divinations. Detection, revelation, and Scrying effects pass right over you, your possessions, and your auras, detecting nothing unless the detecting effect has a counteract level of 20 or higher. For example, detect magic would still detect other magic in the area but not any magic on you, true seeing wouldn’t reveal you, locate or Scrying wouldn’t find you, and so on.
How could a caster arrive to a counteract level of 20?
Level 35 caster using a level 17 spell slot while rolling a critical success.
However this either is a typo (like the dreaded Clay Golem ability) and the counteract level is supposed to be 10 (there seem to be a lot of Rogue abilities that have character level = counteract level whereas it must be 1/2 character level) or only meant to be beat by powerful artifacts or divine intervention.
Dispelling Slice also features this kind of "nonsense":
Your sneak attack slices through the threads binding magic to a target. Make a Strike against a flat-footed creature (your choice). If your Strike deals sneak attack damage, you attempt to counteract a single spell active on the target. Your counteract level is equal to your rogue level, and your counteract check modifier is equal to your class DC – 10.