Hi there ^^
Here are the synergies i know (Correct me if i'm wrong or i miss something):
RoL Hope / Making the enemy to deal magic damage (Quintessence + SoW) while you have the Mirror Shield. This duo is centered in void/avoid the enemy (Phase Shield/Silence/Hope+Spam of RoL)
Disadvantages: No permanent control. RoL is easy to kill, so make sure you can fractal them after sending those small critters to the field. Most of the monsters demands too much quanta without having very good abilities in this duo.
Crusaders turned to Vampires covered by Cloacks (If the enemy doesn't have permanent control he cant touch you by targeting). Also you won't need too much Darkness quanta, so cloacks are really easy to cast. Duo bassed on stealing HP.
Disadvantages: Against a deck whose strategy is affect your quanta pool or pillars/pendulumns (unless you got a sanctuary fast) you are screwed.
Blessing Dune Scorpion / Blessing Deja Vus + using its ability + Luciferase + Hope (1 deja vu = +2 defense) / Sundials and Hourglasses will make you draw cards like crazy while Rewind and Eternity will drive crazy your enemy. Duo bassed on blessing specific creatures.
Disadvantages: No permanent control and the only creature control that you have is Rewind/Eternity (so, against a rush deck, if u dont draw fast, prepare to rage quit)
If you are using the Blessing decks based on Deja Vus and Dune Scorpions you are weak to card control (You have no chance against decks like Neptune or Octane.)
Blessing Wyrms and Pegasus to expand the dive damage and then using Sky Blitz to expand it even more (If you have Shard Of Freedom you can do a massive damage) / Crusaders + Eagle's Eye (Crusaders got card control and airbone as passive ability, so they will be afected by Shard of Freedom and Sky Blitz.)
This synergy is bassed on damage. My favorite synergy ^^
Disadvantages: Both creatures with dive ability doesn't have much HP, so they are easy to kill if they aren't blessed. No permanent control (An enemy with cloacks like Jezebel would be imposible to face if you are using the crusader version. Also players who likes to spam Shard of Gratitude or Empathic Bonds while they are using Aflaxtonix on their creatures or spaming monsters will slow/stop most part of your damage and she/he will have time to see how to take care of you.)
Slows opponent (Congealing his/her monsters, Inundation, Ice Lance on his weapon, Permafrost Shield). Protects you with Sanctuary (Decks like Decay will be useless, decks centered on Black Hole/Nightmare/Silence are slowed or annulled) and Purify (Decks like Scorpio and Serket are quite slow against you) . You can use Luciferase on Abyss Crawler + Hope + Shard of Patience. Nymph's Tears = A lot of Light Nymphs healing you over and over again.
As you can see this duo is centered in defense, it can stops or slows a lot of decks.
Disadvantages: Doesn't have permanent control. It isn't a fast deck and can't deal a big damage cause most of the water monsters needs another quanta element to work, so, against a fast deck that is not monster rush you are in danger.
Rage Elixir + Archangel + Heal / Untargetable Seraphs. Blessing can support any strategy here. You can deal a big damage. Fire has the permanent and the creature control while Light has the defensive ability to heal you or your monsters and expand your life. I really like this duo.
Disadvantages: If you don't draw a Rage Elixir fast you won't give so much damage. Seraph is high quanta cost. You are really weak against decks like Destiny, Seism and Voodoo Dolls + Basilisk Blood + Gravity Force.
A lot of synergy here! Leaf Dragon + Light Pillars (With even only the Life Mark) + Jade Dragons or anything you want, monsters are low quanta cost. You can have a rush deck like Ferox or one based on health, quite easy to win with full HP. both are good with this duo. You can use Adrenaline on your endowed Crusaders to regenerate a lot of times per turn at the same time that you have Spine Carapace (It will kill the enemy's monsters slowly but successfully and the damage done by your enemy is recovered by Crusaders, Light Nymphs if you have, Feral Bonds or/and Shards of Gratitude, so... when their monsters are gone your health will raise like crazy!) Divine Glory is nothing against decks like this, even if you let him uses his miracles. Octane is quite slowed. The power of regeneration! Also you can use Luciferase on your Giant Frogs and Cockatrices and then hope, as i said they are cheap to play.
This deck is centered on speed. (Some decks in regeneration too.)
Disadvantages: No permanent control and almost nothing in creature control (Only Spine Carapace). This duo is really weak when it must face Otyugh and bunches of Fire Storms, even with Archangels (Most of the creatures has low HP and will be dead instantly.)
Stone Skin + Shard of Divinite + Miracle / Luciferase on Steel Golems (9 HP, are hard to kill) + Hope / Iridium Warden + Blessing. This duo has a lot of defense (Iridium Warden / SS / SoD / Miracle / Basilisk Blood / Sanctuary / Diamond Shield) You can make the enemy rage quit! A lot of times if he/she doesn't kill you fast.. decked out! Facing decks like these is really annoying. Duo centered at expanding HP.
Disadvantages: Low and slow at attack, no permanent control (Pulverizer needs gravity quanta) and the only effect that you can do on your enemy's monsters is delay [except when Iridium Wardens are blessed, so they make damage (airbone creatures aren't affected by the damage, only delayed)]
Gravition Salvager (Recovering destroyed permanents) or Gravition Guard (Low quanta cost and high HP) + Luciferase + Hope / Crusaders + Titan / Blessed Otyughs (Low and Medium HP entities) + Gravity Shield (High HP entities) / Angels + Armagios (Overdrive in some decks) / Shard of Focus + Gravity Force is devasting for permanents / A lot of strategies here! And you can boost your self with sundials (Upgraded ones has no quanta cost at cast and 1
to hasten) or stop the attack from rush decks while Otyugh is taking care of them. Gravity Force can helps to kill some annoying monster that the Otyugh can't eat, like some Nymphs or some Dragons. Also Chimera is great when you are not using Momentum. Overdrive can be used to delete an enemy monster ability if you don't have a Otyugh. This duo has a big defense and a good offense, specially to permanents and monsters; it's quite balanced.
Disadvantages: This duo is usually a bit slow, or at least the most part of its decks, so, in my opinion, you'll need Sundial (Drawing cards is quite important when your deck isn't fast or balanced). Otyugh can be avoided by Rewind, Crusaders too... like the Armagios with Overdrive or/and Gravity Force. Mutation is quite annoying here too! So watch out, you must have the cards to counter the permanent and card control on the table before your enemy does. That's the reason i think it needs speed.
Poison + Sundials + Shards of Divinity and Sacrifice / Aflaxtonix + Solar Shield + a lot of Light Dragons / Deathstalker + Blessing + Tons of Poison. I really can't find too much here, maybe Luciferase with Mummies but they are easy to kill and it's a waste of time considering that the enemy can be beaten by a Poison rush and Mummies. Decks with Quicksand and Black Hole aren't so effective because you need low quanta to play your cards. Decks in this duo are centered on fast Poison.
Disadvantages: If the enemy has a defensive strategy you become slow, better not to talk if he/she has Purify. This duo doesn't have permanent control and the creature control is Plague, so if you don't kill the enemy fast his/her monsters will kick your ass. Rush decks are mean here, you will need Sundials.
Photon + Mutation / A lot of Micro Abominations + Luciferase + Hope (doesn't look very well at long games) / Antimatter (Powerful monsters) + Dissipation Shield (Absorbs weak monsters's damage) / Micro Abominations + Butterfly Effect + Blessing or/and Chaos Power to prevent being killed (You will have constantly permanent control because it's a low quanta card; it can be summoned fast and the enemy will must think well what permanent to cast) / Maxwell's Demon + Blessing/Chaos Power + Pandemonium (Enemy's monsters loses HP at most of the cases and Max will be able to take care of them.)
This duo isn't centered in anything except mutations and randomness, Chaos...
Disadvantages: Quite slow at damage except if you have luck mutating. Rush decks are annoying (Discord might help), specially rainbows. There is not much useful synergy; you only become annoying to the opponent because this duo doesn't have fast and high damage. Your best chance is to have fast permanent and card control (that way the enemy will become slow and you will gain time to kill him/her)
I took a time writing this Post. Hope you can find something useful