Here's a 5 color Dragon deck I'm making based off of Sarkhan and Nicol Bolas's abilities as well as certain cards like Vaevictis Asmadi, the Dire and Bolas's Sister Palladia-Mors, the Ruiner.
All suggestions are welcome
This Deck specializes in using burn spells to begin with a safe environment for later as we'll achieve having our dragons in play on a near to completely cleared board.
Certain spells like Shock, Lightning Strike and partially Spit Flame will all be used as slaying spells to keep us safe for when dragons arrive.
Cards like Dragon's Hoard and Sarkhan, Fireblood are great cards to use for ramp that allows us to search for what we may need in order to summon the mighty dragons and to cast any extra spells to keep them safe.
Have some various lands such as Dragonskull Summit and Unclaimed Territory to use so that we have alternative ways to use our dragons. It'll be useful if we were to lose Sarkhan. On the other hand Sulfur Falls is a good addition shall we need it for Nicol Bolas, the Ravager
if we aren't to get any dragon's hoard or sarkhan early on.
Finally we got Dragons plus a Pyromancer, being as fierce as they are said to be here's a nice short breakdown of each one:
Demanding Dragon - This dragon demands only one thing, a creature to sacrifice of your opponets or 5 of their life total. Getting this creatures ability to sacrifice a creature of theirs really helps against other mid-range matchups for they won't have as many tough creatures to save themselves against this winged beast.
Vaevictis Asmadi, the Dire - Dragon's being as fierce as Vaevictis causes each of you to sacrifice something regardless of what it may be, lands, creatures, planeswalkers, enchantments. However only when he attacks.
Palladia-Mors, the Ruiner - Bolas's Sister, nice creature with hexproof til it deals damage and has the nice abilities of flight, vigilance and trample. Keeping it safe can really benefit for a time
Nicol Bolas, the Ravager
/arisen - As many know, this card is becoming one of the best cards in standard, mainly due to it discarding a card off your opponet each time you are able to summon/re-summon him and for his Arisen form, grants the deadly abilities that causes him to do up to 10 damage towards creature or planeswalker, drawing two cards to up the loyalty counters, raise the dead of a fellow dragon who has fallen in battle or slain through magical means, and lastly to basically just win the game by exiling all but bottom of target players library. This card has so much potential to it, it nearly seems almost unbeatable without a good counter or ways to slay it quick.
Lathliss, Dragon Queen - A nice dragon queen who helps gives more dragons out should there be extra dragons you would like to summon, plus another 5/5 token on the side. This can benefit if your running low on singular dragons and need some more. Summonable by turn 4 at the earliest as like palladia and vaevictis.
Dismissive Pyromancer - A card not many people know about to much that I happen to really enjoy for its ability to sacrifice for 4 damage to any target creature and helps with ramp so you shouldn't need cards like tormenting voice as much or at all. Him plus sarkhan/dragons hoard and burn spells means two abilities that are useful for a price of two mana. I enjoy the card for its abilities and if you need to sacrifice it against a stronger creature then it could very well help you out against your opponet.
Niv-Mizzet, Parun - A really great card to use as it can't be countered and also whenever you draw cards which by mid-game you should be doing quite often will allow parun to dish out lots of those 1 damage ability as your constantly drawing cards each turn. Tougher part is to summon him as he's higher up in blue mana but Sarkhan is able to help with that along with sulfur falls
Hellkite Whelp - Honestly I love the looks of this card and its similar to Glorybringer but slightly less powerful however being a 5 drop I can use it for an earlier game dragon and be able to defeat some of those aggro monstrosities that seem to be a pest in early game, Hellkite I'm hoping can help get that job done