I have not been able to find a site that has a breakdown of %'s for drafting purposes... I have 3 cards in my splash... running 5 sources of that color. That reasonable? unflinching courage, summoner, and the rtr g/w pump spell.
Summoner is up for debate, but you should be able to pick up some curve toppers in your main colors without too much hassle. It's only really strong if you can actually abuse the creatures somehow (populate) or can bounce and recast the summoner.
I think you just have to cast trostani's summoner. I think ten power for seven mana is strong enough. Populating the rhino off of trostani's summoner seems win more to me.
Three sources for a splash is usually fine, but Common Bond probably should not be splashed off that few, since it isn't good enough to justify the times it sits in your hand.
If you're playing 5 sources of your splash color, then how many sources do you have of your other colors? It's great to make sure your splash is accessible, but you need to cast your other spells too.
At least one of those forests should be a plains. 7 sources is the bare minimum required to play a color, while 5 is excessive for most splashes. You need to add more white mana so you can reliably cast your white spells, since they make up half your deck.
The general rule is usually how many cards you are splashing + 1 for the number of sources. That being said you want your splashes to be high impact, Common Bond is not something you splash for. The other two are fine if you find your deck to be on the weak side.
Trostani's summoner is absolutely nuts and not splashing for it (if your deck is going for the long game) is a big mistake.
You could definitely get away with cutting a forest and common bond for a blue or white card and whichever land you need the most. A quick survey of which colors have the most 1CC or CC costs (especially CC) should clue you in.
As everyone has said, 3 sources are sufficient for a splash, BUT you should only run cards that are powerful enough to justify the increased manabase inconsistency, and you shouldn't count on being able to cast them before turn 5 or so.
I think you just have to cast trostani's summoner. I think ten power for seven mana is strong enough. Populating the rhino off of trostani's summoner seems win more to me.
*DCI Rules Advisor*
If you're playing 5 sources of your splash color, then how many sources do you have of your other colors? It's great to make sure your splash is accessible, but you need to cast your other spells too.
I have a very even uw split. So I am running 7/7/4. I also have one simic cluestone.
You could definitely get away with cutting a forest and common bond for a blue or white card and whichever land you need the most. A quick survey of which colors have the most 1CC or CC costs (especially CC) should clue you in.
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