From the rules:
How do I meet the Synergy Point requirement?
By playing spells and basic attacks of that element. For example, if an earth spell has an alternate ability with SP 2, and you play 2 other earth spells/earth basic attacks, you can use the alternate ability. You could also play 2 earth basic attacks, 2 earth spells, or 1 earth basic attack and 1 earth spell to meet the requirement.
Which spells/basic attacks count for Synergy Points? All the cards played in a turn, or only those played before the spell with the Synergy Point requirement? (From the wording above, I thought you would play the spells and basic attacks to meet the Synergy Point requirement after you play the card with the requirement.)
Also, does the last sentence in the rule actually add anything to the previous one (as suggested by the use of "also")? If so, what exactly does it add? Or does it just spell out the previous one more explicitly?
Lastly, may you choose to use the basic ability even if you meet the Synergy Point requirement?