High Pressure System vs. Muk ex

[Venusaur]

Does High Pressure system change the amount of damage Muk ex does with slimy water?
I would say no because it just says you pay C less to retreat, not your retreat cost loses a C.

 

[Sensei]

Yes it does.Applicable ruling below.

`Sensei


Q. Does High Pressure system change the amount of damage Muk-EX does
with Slimy Water?
A. Yes, provided that the Pokemon's retreat cost isn't already zero -
there is no such thing as a negative retreat cost. Anything that
reduces the retreat cost will affect the damage Muk-EX does with its Slimy
Water attack. (Feb 5, 2004 PUI Rules Team)