Limiting Deceptive Attack

This idea came to me while I was responding to a post about Psi Wars.

For people who want to cap Deceptive Attack and Prediction Shot in a way that's meaningful when playing with high-bonus equipment, such as ultra-tech weaponry, stacked magical and situational bonuses, and so on, here is a way to do it:


For Deceptive Attack and Prediction Shots (Martial Arts, p. 121), final base and effective weapon skill must both be at least 10.

For example, Dirk Strikelots, Knight For Hire, has Broadsword-20, Slayer Training (Broadsword Swing/Neck), and carries Missnomore, an Accuracy +3 broadsword. His base skill is 20, but his effective skill is 24 (22 vs. the neck).

He's fighting Konk Chopgroin, fierce orc chieftan. He's on Bad Footing (-2 to attack). He knows Konk has some fierce defensive skill and decided to do the most Deceptive Attack possible. He swings to the neck. His effective skill to hit the neck is (20 skill, +3 accuracy, -2 neck, -2 bad footing = 19 skill). His skill 20 would allow him up to a -5 deceptive attack, but that would make his base skill 10 and his effective skill 9, so he has to dial it back to -4. He swings at an effective skill of 11. If it hits, Konk parries at -4! He could choose to hit the torso (-0) instead of the neck (-2) at a 13, or go for Deceptive Attack -5 and stay at an 11. He rolls a 13 and misses.

The next turn, Dirk decides to All-Out Attack (Determined) to ensure he hits. The +4 to hit increases his chances of success, but he can't use it to lower his foes defenses - his skill 20 limits him to a maximum of -5 Deceptive Attack.


Notes:

This adds a lot of complexity. You'll need to know what bonuses/penalties should be included, and which ones should not, and remember to calculate down to a 10 or 11 and then add modifiers back on after that, then re-calculate if your negatives bring you below 10 after all.

Riposte has a similar approach, though, so this isn't a totally new idea for GURPS - you don't get to count shield DB, Shield spells, etc. and turn that into a better Riposte.

The wording might need some work, but this is a good way to avoid bonuses becoming defense-swamping penalties for defenders. It does mean that there will always be a further push to raise base weapon skill - you'll need it to ensure you can Deceptive Attack the way you want to.