Lets say we are in my opponents main phase and I have oh, lets make it fun a {sylvan caryatid} and four {forest} and my opponent plays {anger of the gods} can I tap all my mana sources and play {boon satyr} for its bestow ability during my opponents attack phase? To simplify, can I hold mana from one phase to another?
You cannot, I'm afraid:
500.4. (http://imtgapp.com/forum/index.php?action=imtg;area=rule;number=500.4.): When a step or phase ends, any unused mana left in a player's mana pool empties. This turn-based action doesn't use the stack.
I sort of knew that going into this question but liqueur and a lack of common sence prevailed😜thanks for the quick reply tho😃
unless you have {omnath, locus of mana}.
You can't cast the boon satyr during your opponents attack phase, but the flash will allow you to cast it in response to their burn spell during their main phase.
I believe that was the question you really wanted answered.
Will look for rules, but I want to say flash changes when you can cast a spell, and bestow is an alternate casting cost so it still counts as being cast and is affected by flash.
Ruling on boon satyr:
9/15/2013 You don't choose whether the spell is going to be an Aura spell or not until the spell is already on the stack. Abilities that affect when you can cast a spell, such as flash, will apply to the creature card in whatever zone you're casting it from. For example, an effect that said you can cast creature spells as though they have flash will allow you to cast a creature card with bestow as an Aura spell anytime you could cast an instant.
You may tap out in response to his {anger of the gods}, giving you 5 total mana. Then if youd like to wait for anger of the gods to resolve, you could then cast {boon satyr} during THAT phase, dodging the wrath with your boon. However you will be SOL if you really must cast it during their attack phase. The good news is youd be just as well off casting it during their main phase, because even if mana carried over theyd know something major was up with that 5 open mana, ruining the surprise of your combat trick. Anyways, i ramble when im tired