I personally don't like the Barcgal, Llew, Flogal combo. It requires you to be at a disadvantage from the start to get all the benefits. Barcgal may only have to rest for his effect, but Llew requires a Counter Blast for his effect to take root. Not only that, you only have two pieces to the puzzle there. You still require Flogal in order to execute this maneuver; another trigger unit. It would be unfortunate to have mulliganned into Flogal, due to her usefulness as a trigger being in the deck. As stated before, Llew being a counterblast ability, you wouldn't be able to use it until your second turn at the earliest. Moving on, the entire reason one would want to ride for Blaster Blader is to use his effect to retire an opposing rearguard; a Counter Blast 2 effect. Meaning you will have needed to acquire 3 damage by turn 2: In which case I worry for turn 4.
It is a card for the one with the least luck possible. By this, I mean, Your opening hand did not consist of either a Grade 2 (Such as Blaster Blade) or Gancelot (To Search Blaster Blade) (Also a must have at max for Blaster Blade Decks); unfortunate, but possible. On Turn 1, Ride for a Grade 1 to get Barcgal (If you run Llew and not Barkgal, then you clearly need to take another look at your deck) into a back RG Circle (He must be alive for Llew's ability) and rest him for either Llew or Flogal. There will be no chance to use Llew's effect on your first turn due to the lack of your opponent's ability to attack. On turn 3 (Your second turn) Use Barcgal's effect again to call the other unit you had not called the turn prior (Assuming you did not ride to Grade 2 this turn) and counterblast 1 (assuming you took damage last turn) to put it all into your soul and Ride Blaster Blader.
This can actually be more useful, not as a card to get out Blaster Blader, but as a card to increase your soul early on. With the combo said and done, you have Llew, Barkgal, Flogal, and your Grade 1 in your soul. That's already 4 cards by turn 3 at the cost of 1 counter blast.
Strategies and game play:
Using this card in a deck more designed to Soul (Or Mega) blast would be interesting, and significantly more reliable than the shambles people try to make out of it when superior riding for Blaster Blader. Blaster Blader is a great card, but difficult to use correctly early game like that, and he is a Grade 2 (Obviously), meaning there is room for more to be done.
Combos with other cards:
As I've been pressing. Getting out Blaster Blader is more of an obvious means to an end than the actual end itself. You have your soul Fueled, now when the Blader joins them for a total of 5, that is just enough for Soul Saver Dragon's Soul blast, boosting 3 of your units by 5k each.
Who says the first thing you do is superior ride for Blaster Blader? Call a few Young Pegasus knights to get a 3k boost from putting cards into your soul.
Borugal and Gigantech Dozer both get boosts from themselves during your turn while you cave 6 or more cards in your Soul, so just drop a Margal or a Silent Sage Sharon to give that extra push as well as a bonus 3k to any Royal Paladin.
Ways to counteract it:
Don't attack right off the get go. Before any of this can go off, your opponent needs that one damage for a counterblast, and 3 for it to be devastating. If you hold off on your attack for one turn, it would no longer be profitable for your opponent to waste time trying to set up Llew, unless their hand was really that bad after a mulligan and 2~3 turns of drawing/drive checking.
Another is to get rid of Barcgal. Your opponent should only have 1 of it in their deck, so if you are able to retire that quickly, Llew is sitting stupid in the rearguard.
Pulls Blaster Blader out of the deck quickly
Increases Soul quickly and efficiently
Requirements make set-up for his ability easy and inexpensive early game.
Using his ability implies that your deck is short 2 trigger units.
Strength isn't threatening.
Very small window of use.
Requires all 3 units for his ability to work.
Double Rare in Descent of the King of Knights is the only known print.
Artwork and aesthetics:
The foil effect on the card makes sort of disrupts the feel that it isn't of greatness yet.
Despite his many uses, there are still other, better ways of locating and riding Blaster Blader. One would already have ridden him if Gancelot was in the opening hand or any one of the two draws, if he wasn't in hand to begin with. The chance of you actually needing Llew like this is only 36%, significant, but still more likely that you can ride Blaster Blader normally (This is taking into account that Gancelot's ability occurs during the Main Phase and is therefore slower than Llew given the second draw phase and ignoring any draw triggers/damage checks). And Cards like Margal and Silent Sage Sharon already increase the soul, and provide a boost to your units, unlike Llew.