|I'm able to answer any and all questions related to the English Yu-Gi-Oh! game itself. This includes, but isn't limited to:
Deck Fixes: Either making suggestions and improvements on a deck you've already built, or building a deck from scratch for you. In either case, please give an idea of the kind of deck you're building, the level of play you're planning to use it in (small tournaments, regionals etc), and the kind of budget you're on.
Please format decks in a way that's easy to read. Each card name should be on its own line, with a number before it indicating how many you're playing. Please split decks into Monsters, Spells and Traps.
NOTE: A level of reasonability is assumed with this. I cannot build you a nationals winning deck based on monsters whose name starts with the Letter 'A' on a budget of £4($6)... Nor will I generally respond well to Questions touting "No Xyz, Synchro... etc" or disallowing cards from certain parts of the show. I haven't seen the show in a number of years and find these conditions to usually be poorly-defined.
Rulings: On any card interacting with any other card(s). Tell .....
Welp, that's what I get for not reading cards and just assuming they work without the old terrible versions like most themes do. My Fault. You'll have to drop Bulb, Breakthrough Skill and probably Reinforcement
There are a couple of things that I'm not a fan of here - which we'll go through in turn. Firstly - this deck seems to lack a focus - what exactly are you trying to do here - I get that you're going
So in answer to your first question: Yes, you can activate Gamma's Effect when your opponent declares an attack. Effects that have restrictions on when during your opponent's turn you can use them
Unfortunately falling prey to Spell/Trap effects is one of the Downsides of the Blue-Eyes deck if you haven't already established a board. You can try to counter these with Spell/Trap Removal like Twin
If you're already at 50 cards here, then you may as well go all the way to 60 and make "That Grass is Greener" as good as it can be. Immediately milling 20-ish is probably going to enable a number of