i dont know how to do it，but i just review a rank math，
the player i against only got 500 stone and delete first canal。 then all canal he build become only cost 50 stone
Your “Canal” mean Byzentine Cistern? And that if you delete 1st Cistern, system will have issue in counting and don’t increase cost to build as it always count exist cistern as 0?
Seem like someone already report: All Byzantine Cistern cost only 50 stones