This is maybe a very similar deck for T1 switch was placed as second place in a tourment.
I have absolutely no idea what the point of that, or the link, was.
Addressing Entomb. This is fundamentally bad because it goes against the gameplan of control slaver. Slaver uses its large draw engine of Thirst for Knowledge + potential Memory Jar to discard threats, as it doesn't need to discard a threat early (an early Slaver usually nets little and an early Pentavus is vulnerable to disruption). In addition such a move would be to move the deck to a more beatdown mode - going for the early Slaver, or Pentavus, which it is clearly not. The Atog Lord already defined why it is so situational, so that does not need to be addressed, but it is also detrimental to the nature of Slaver's gameplan.
Entomb does not add any speed since the turn one Welder is the ideal drop there. On turn two, with a set of moxen this is either the TFK on first-main-phase turn or the Mana Drain turn (it's also ideal to drop a Slaver off Drain mana too, obviously). The Slaver/Pentavus/Platinum is usually the crown of the tempo control slaver has gained through its massive draw or control elements (either TFK or Drain). Thus, in reality, it does not really provide the speed the deck is looking for, nor fit into the plan of the deck. Once the TFK engine can get going - or once the game simply progresses, getting a card into the grave either through the TFK or by getting it countered is merely a formality.
Also, the idea here focuses on The Atog Lord's second point - you must have artifacts in play to weld. Currently, this is the biggest difficulty in using Slaver, that Shaman or artifact destruction are keeping it from using Welder, and Entomb does not address this. Of course, postsideboard, this becomes amplified as more Shamans will enter from the key decks (Hulk, the mirror) that you must keep into account. This is the problem that needs to be addressed - not dumping a card into the graveyard.
Looking at control slaver and Hulk. In the mirror Entomb provides very little advantage for obvious reasons concerning tempo and your opponent's available cards. Although getting out an early Slaver helps versus Hulk, game one, you do have an advantage over them through your threats, and a slaver means less without a Tog - meaning it's best to late the progression of the game drop cards in the grave. Game two, it's all about Blood Moon since their Shamans go a long way to negating your Welders. Thus cards you add in should be to improve these two matchups primarily. Entomb is a niche card. This is not its deck.
