RulingHall of Heroes (rules 1.0–1.4)
Expansion card questions: Can I play a zero-cost card, such as Assess the Situation (Ant-Man #33), and ‘overpay’ for it using, say,…
Question
Can I play a zero-cost card, such as Assess the Situation (Ant-Man #33), and ‘overpay’ for it using, say, Innovation (The Mad Titan’s Shadow #58), in order to benefit from Innovation’s Hero Response?
Answer
Because Innovation specifies “after you spend this card”, not “after you pay for” another card with it, you could “spend” it while playing a 0 cost card.
— Alex Werner, FFG Game Rules Specialist