Play only if
- there is a suitable card to gain in player’s buy rules
Play priority will be higher if
- the player wants to gain an action card with the Ironworks
- if player has more actions in hand, the buy rules will be scanned for an action card to gain
- if player has no more actions in hand, the buy rules will be scanned for the most desired card costing 4 or less
Use if still in action phase (=1) in buy rule condition to gain cards with Ironworks that you don’t actually want to buy (like Great Hall).