Professor Hojo

Professor Hojo's first ability reduces only the amount of generic mana in the first activated ability you activate during your turn that targets a creature. For example, it will reduce an activation cost of 2 generic mana to 0 generic mana , but it will have no effect on an activation cost of green mana .

Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keyword abilities (such as equip) are activated abilities and will have a colon in their reminder text.

Professor Hojo's last ability resolves before the activated ability that caused it to trigger. It resolves even if that activated ability is countered or otherwise leaves the stack.