[FIC] Implement Lifestream's Blessing

[balazskristof]

Implements Lifestream's Blessing

[Susucre]

X needs to be frozen at time of cast. i.e. If you cast Giant Growth or your biggest creature gets removed in response, it should not change how many cards are drawn.

This is definitively something that already got resolved in the past, I'll search for an example of implementation.

[Susucre]

Uhm most of the examples I find are different as they have X alter targetting or damage distribution.

Maybe do something similar to [[Steer Clear]] or [[Lethal Exploit]], storing with a Watcher the greatest power at time of cast?

[theelk801]

I'm pretty sure that's not true, it would matter for effects that care about X targets or distributing X damage, but here it just checks on resolution.

[Jmlundeen]

It should be snapshot at the time of cast, not resolution. Monstrous Onslaught is similar and the rules notes

You divide the damage among the target creatures as you cast Monstrous Onslaught. Each target must be assigned at least 1 damage.
(2020-11-10)
The value of X is determined at the time you divide damage. It won't change later, even if the greatest power among creatures you control changes.
(2020-11-10)

[theelk801]

That's different as it's using the X value for targeting, whereas here it only checks on resolution. Here's a ruling for [[Intelligence Bobblehead]]:

The value of X is determined only once, as Intelligence Bobblehead’s last ability resolves.

[theelk801]

oh lol no I'm making fun of myself we're good

[Jmlundeen]

Edit: ok I'm not sure anymore, should the list of creatures to look at be snapshotted at time of cast, or the greatest power among they on time of cast?

It should snapshot the greatest power, not list of creatures

[JayDi85]

It's auto-announce value. Instead watcher (also good solution btw) you can use CostAdjuster and override prepareX to calculate and set X value in the time of cast. See example with ImprintedManaValueXCostAdjuster.

Also there are special LockedInDynamicValue that can save calculation value, but I'm not sure about good usage (only one card support it).

[JayDi85]

X value must be stored in cost or directly in getSourceCostsTagsMap, so useful methods:

• CardUtil.getSourceCostsTag(game, source, "X", 0)
• Map<String, Object> tagsMap = CardUtil.getSourceCostsTagsMap(game, needObject.getSpellAbility());
• tagsMap.put("X", 123);

[ssk97]

CostsTagsMap is for values that get copied when the spell does, primarily for storing how costs were paid. Going by the ruling on [[Orator of Ojutai]], I think that copying this spell should mean the copy has X=0?