For future ones? No. Ayumi has these, though:

https://ayumilove.net/raid-shadow-legends-summoning-event-calendar/

https://ayumilove.net/raid-shadow-legends-guaranteed-champion-summon-event/

Ayumi calendar does look to be a bit off at the moment - likely thrown off due to the 2x weekend that happened around New Years, one for each shard type. 

That said, schedule alternates every weekend between 2x/10x and the 2x (rarity boost) events follow in alphabetical order:

Ancient, Sacred, Void. We just had Voids last weekend, which means Ancients will begin on the 24th. Then Sacred 2x on March 3rd, Void 2x on March 17th.  

For 10x (gives you a 10x chance on specific champions IF if you hit a specific rarity from your pull. does not boost your chances of pulling the rarities.) they are somewhat random. There are other shard events as listed in the link kram posted but most players want to be targeting 2x events. 

Hellhades has a decent counter until next shard event but isnt perfect either and plarium can switch whenever it wants , its simply a countdown to next shard event based on previous ones ! Although his CvC countdown is usually spot on .

When is the next free ledgendary event?

Like the one were we could earn a free ledgendary by play 7 days

Good news! it started 4 days ago!

hello... I need help with the name of the song on the main page of PLARIUM/RAID SHADOW LEGENDS (with a dragon) a melody is played on a flute. PLEASE TELL ME THE NAME OF THE SONG