Other than the general hatred of Matt Ward, is there a reason you want to throw him into a volcano?
He wrote the Grey Knights book and that book is the most poorly written book in the game. The fluff is garbage and portrays the Knights as these perfect demonhunters who literally cannot be corrupted... despite the fact that the entire Chapter is made up of Psykers. There are two things in the book that are so bad that even the most die hard Grey Knight defenders have difficult excusing.
First, there is an account of a time where the Grey Knights killed a regiment of Sisters of Battle and then covered their armor with Sister of Battle blood. It's excused as making them harder to corrupt, which makes no fucking sense that killing things and bathing in the blood of the things you killed totally isn't something Khorne followers would do, not at all!
Second, Chapter Master Keldor Draigo. A character that is such a fucking Mary Sue that I have yet to meet someone who defends the fluff around him, even if they use him for being really fucking powerful (though I would wager that Logan Grimnar, the Great Wolf (Space Wolves Chapter Master) is a bit more powerful on the table). His fluff is that, after a battle where he killed a demon prince, he was cursed to be sucked into the Warp. He is trapped there for as long as he lives... but he can't be corrupted. Why because he's a Grey Knight and Grey Knights are so pure, that they can NEVER be corrupted... even though they're all Psykers. Furthermore, not only is he constantly fighting the Forces of Chaos in the Warp with no rest, which makes no sense already, he will occasionally be transported back into real space, chasing after the demons that are heading out to fight the Grey Knights. And he's still completely uncorrupted. Hell, Inquisitors don't even make the logical assumption of him being corrupted because he's a PURE AND UNCORRUPTABLE GREY KNIGHT!!! That, I especially call bullshit on because an Inquisitor working with the Grey Knights would watch him walk out of a Warp portal and immediately tell the Grey Knight Captain he was fighting with to blast Draigo with a fucking Lascannon because there is no fucking way a Psyker could spend any significant amount of time in the warp and walk out uncorrupted.
Their rules can get pretty ridiculous, as well. Unrestricted Terminator troops choices! Even Dark Angels have to buy the right HQ to do that. The Nemesis Dreadknight! Which is one of the most horribly overpowered units in the game with a rather low points cost (130 points), two free Dreadnought Close Combat Weapons (which pushes its strength from 6 to 10 and gives it an extra attack), an option for a Personal Teleporter and the fact that it's a Monstrous Creature with a 2+ Armor Save in the first place. Compare this to the fact that Dreadnoughts cost 105 points and aren't even close to as powerful as a Dreadknight with no options.
While there is some other stuff that people point to when criticizing Grey Knight rules, the Dreadknight is probably the most bullshit thing that Matt Ward has ever written. But that's not all he's written.
He wrote Blood Angels, which has fluff that included a story of Blood Angels and Necrons teaming up against Tyranids. On its own, this isn't a bad idea as it highlights how much of a threat the Tyranids are. The problem is the fact that, after fighting off the Tyranids, both the Blood Angels and the Necrons just turned around and left, which would never fucking happen. After fighting off the Tyranids, they should have gone back to shooting each other.
Plus, there's the fact that due to being able to take Assault Marines as Troops and the rule that gives discounts on transports if you remove Assault Marine Jump Packs, a Blood Angels player can actually make a better Leaf Blower tank list than the Imperial Guard. AND there's the fact that all of their vehicles are Fast, with the exception of the Land Raider, which can Deepstrike instead AND the fact that their special Predator, the Baal Predator (which has some bullshit fluff around it) is not just Fast, but also a Scout, meaning that a fucking TANK can sneak around the battlefield and enter the game behind enemy lines.
And Ward also wrote the 5th Edition Space Marines book, which has nothing too bad in terms of rules as it's largely just an update to previous rules, but the fluff can only be described as Ultramarines worship. According to that book, there are three kinds of Marine Chapters: Ultramarines and their successors, Chapters that want to be Ultramarines and rogue Chapters that don't and are dying off as a result. Yeah, because the Space Wolves being 10,000 men strong means that they're struggling to survive. Alternatively, tell the Space Wolves that they want to be Ultramarines and count how long before you're either laughed out the airlock or one of them punches you through a wall in anger.
His Warhammer Fantasy Daemons of Chaos book BROKE 7th Edition Warhammer Fantasy. Tournament organizers would often do things like house rule a 2000 point tournament that Daemons players were restricted to 1500 points because of how unbelievably overpowered they were.
His White Dwarf Sisters of Battle Codex is regarded as almost unplayable because it is extremely underpowered.
His Necrons Codex is the best book he's written... and it still sucks. Necron Warriors are completely worthless since Immortals are available as Troops and there's no incentive to not take three squads of Immortals instead of four squads of Warriors. Scarabs make Land Raiders into Swiss Cheese and are Beasts, meaning that they can move around the board VERY quickly, even if they can't free Assault at 12'' anymore. The Doom Scythe is the most powerful Flyer in the game... and Necron players can take three of them and NINE of their Transport variant, the Night Scythe, which means that Necrons can take more flyers than any other army will ever likely be able to take and the Night Scythe, while not half as bad as the Doom Scythe is nothing to sneeze at.
The Doom Scythe, however, is ridiculous. Unlike all of the other Necron vehicles, it does not have Quantum Shielding, which is about the only lucky break you get against it. It's cheap. It's only 175 points. It has a Strength 10 beam weapon that can hit at practically any angle and it has a rather powerful secondary gun that it can also fire with no restrictions due to the nature of Flyers. Being a Flyer, it can also zoom around the board with practically nothing getting in its way and, also due to being a Flyer, it is difficult to hit if you don't have weapons with Skyfire as shooting at Flyers without Skyfire means that you're shooting at Balistics Skill 1.
Compare that to a Space Marine Predator with Twin-Linked Lascannons and Heavy Bolter Sponsons. It's 130 points for that tank. And the Predator is a good tank. Even better comparison: A Tau Hammerhead with Railgun. With no other options, that Hammerhead is 150 points. It is also a good tank, especially with it's large variety of cheap options. The Doom Scythe is FAR more powerful than what an extra 25-45 points warrants.
I hope that helps demonstrate why people hate Matt Ward.
As for painting lessons, I will probably be painting my Fanticide minis, which will give me an introduction to the skill. They are a lot less intricate than 40K figures, but will still give the idea.
That's actually a really good idea.
