In the rules under the glossary section it says that a monster is considered attacking/performing an attack only if it rolls at least one claw symbol. It also says:
- Cards which increase the damage of an attack don't do anything unless you have one claw symbol.
- Attacks that are reduced by other effects and do zero damage are not considered "attacks"for the purposes of cards like Poison Spit.
- If a card deals damage when purchased (like Gas Refinery), this is not considered an attack. Monsters can not yield Tokyo based on this damage, and cards that affect attacks do not affect these cards.
I stand corrected then, cheers for the tip!