[2020] There's a new Crit/Lethality item on PBE/Prepatch called 'The Collector', which loses 10 AD when you combine the components.

This item costs 3000g, builds out of a Serrated Dirk (30 AD), a Pickaxe (25 AD), and a crit cloak.

For the combine cost of 450g, you lose 10 AD for a net 45 instead of the expected 55.

Of course, you still get the Collector's passive (any damage executes targets below 5% HP) but it still feels really bad to lose 10 AD for gold. Noone anywhere is talking about this, and they said they'd be fixing combine stat bugs like this one, but it's 3 days until preseason now and it's been on the PBE since day one.