Missed! symbol cards against Slab the Killer
You can play any card with the Missed! symbol against Slab the Killer, however you will need a total of 2 of them in order to miss. What the means is if you only have one card that you can play and it lets you draw card after you use it, you can play the card, draw your card and if it provide you with a second Missed! symbol you can then play it and miss the shot. If you do not get another card that lets you miss you will still take the hit even though you played one miss card.