Tower: =5N
Stock: =4N
Not sure what to make of this. Given how my Unliving deck games go, I'd expect to be losing tower, gems, and recruits. I guess the hope is to be using this as a finisher or having another card on hand to use use the refunded bricks (plus another 4x brick production with keyword effect) immediately afterward.
Losing tower for this is almost guaranteed in Long Mode. If my opponent were chipping away at my tower in a hidden game, I would have spent bricks to rebuild as a safety measure rather than continuing to save up for this card, and you would want to play it was soon as you had the 60 bricks since any extra would be eliminated before the stock is set to 4N.