Cathodion
Artifact Creature — Construct
When this creature dies, add 
.
Cathodions repair the Great Furnace by soldering parts of themselves to the mechanism. Eventually, they become one with the machine.
Eric Peterson
Mirrodin (MRD)
• #149Rulings
The triggered ability isn't a mana ability. It uses the stack and can be responded to.
(wotc • 2011-01-25)
You get the mana whether you want it or not. If you don't spend it, it will disappear at the end of the current step (or phase).
(wotc • 2011-01-25)
The ability is never a mana ability.
(wotc • 2004-10-04)
Rulings
The triggered ability isn't a mana ability. It uses the stack and can be responded to.
(wotc • 2011-01-25)
You get the mana whether you want it or not. If you don't spend it, it will disappear at the end of the current step (or phase).
(wotc • 2011-01-25)
The ability is never a mana ability.
(wotc • 2004-10-04)