[confirmed]Khalni Hydra + Lodestone Golem

by **Korath** » 19 Nov 2015, 13:37

Describe the Bug:
I have eleven various green creatures (random mana elves) and a two Forest on the bf; AI has two Lodestone Golem. Casting cost for the Khalni Hydra in my hand is {2}

.

Which card did behave improperly ?
Maybe Khalni Hydra. More likely the cost modification engine again.

Which update are you using?(date,name)Which type(Duel,Gauntlet,Sealed Deck)
FRF.

What exactly should be the correct behavior/interaction ?
Free. The golems increase the casting cost to {2}

and eight green; then the hydra's ability reduces that by eleven green.

Comp rules:
117.7b If a cost is reduced by an amount of colored mana that exceeds its mana component of that color, the cost's mana component of that color is reduced to nothing and the cost's generic mana component is reduced by the difference.

Khalni Hydra even has a ruling specific to this case, now that I think to check for it:
6/15/2010 If an effect (such as the one from Lodestone Golem) imposes an additional generic mana cost to casting Khalni Hydra, the Hydra's ability will reduce it too. It'll reduce the amount of green mana you need to spend first, though.

Are any other cards possibly affected by this bug ?
Stupidly enough, there's only three cards that reduce mana costs by a specific colored amount, and the other two (Edgewalker and Ragemonger) both say that rule doesn't apply to them.

This is a fairly esoteric corner case. I wouldn't bring it up, but I'm currently fighting with it in Shandalar, and in order to make the headaches go away, I have to share them.