- destroys ALL nonland permanents (‘walkers included!)
- costs 3 + 5
- in real world terms, pretty cheap (~$5)
- In a very tight section
- costs 5 mana to activate
Wrath effects are powerful. That’s why they feature in cube so heavily. Each colour except green has some sort of wrath – even red, the aggro colour, has 3 in my cube – pyroclasm , wildfire and crater hellion. So it makes sense to get some colourless ones. Black is a powerful colour in many ways – it’s ability to neuter creatures is unmatched. When paired up with red, planeswalkers, creatures,lands and artifacts are nothing, since there are plenty of cards to deal with them in those colours. There’s one problem supertype though – enchantments. O stone lets RB decks kill enchantments.
In UG, what’s the problem supertype? Awfully, it’s creatures. WB? Artifacts (barring disenchant). UB? Lands. Obviously there are exceptions to this rule, but in general, black can’t deal with artifacts and enchantments, red can’t deal with enchantments or big creatures, green can’t deal with creatures (other than with bigger creatures), white can’t deal with more than 2 artifacts / enchantments, and blue can’t deal with anything permanently short of countering it. Obviously this leaves gaps, which can be filled by the colourless section. O-stone really helps here, since it can destroy any problem permanents for a colour pair.
O-stone also has all the benefits of a conventional wrath effect – creating CA, coming back from a disadvantageous board. It can also be noted that due to it’s 3cmc, there’s some shenanigans with a blink deck and sun titan to be had.
Finally, it can be noted that in a really slow game, you can always drop some fate counters on a planeswalker and a couple creatures, then wipe and go to town on them! I would say I crack it without any fate counters more often than with fate counters.