I noticed you were looking at recurring cards, ideally repeatedly? If you just want creatures back one of the best solutions is Demon of Dark Schemes, this can be part of an infinite combo fairly easily (see stuff like Warren Soultrader and Mitotic Slime, maybe a Zulaport Cutthroat), and it can kill off a ton of weenies sometimes to boot.

If you like Gisela and Hidetsugu, you might also like Vito, Thorn of the Dusk Rose! If he gives Hidetsugu Lifelink you'll not only not die, you'll gain life, and Vito's static will then allow you to kill whomever is the biggest threat! If you can repeat it you can win on the spot, otherwise you'll probably win next turn. I think Vito's two abilities work with other combat damage strategies fwiw, effectively doubling combat damage to players (in the form of lost life, not Commander damage) for 5 mana isn't bad, especially when you're also gaining life, that can be quite a life swing.

I'm not sure how many counters you tend to build up over the course of a game, but I love using Legacy Weapon in my Sisay, Weatherlight Captain deck as an infinite mana payoff. It'd be a great draw if you've got a bajillion counters and you can't swing, sniping anything you want is pretty handy.

I think something went wrong with my previous post lol, thanks for being understanding!

I meant to ask if Dr Who is a problem too, because I really like The Sound of Drums and Ensnared by the Mara in Red (I use almost no cards from Dr Who). Drums is a nice recursive aura, handy if people wipe the board, and Ensnared is the opponent's choice of damage (possibly quite a bit if they run high MV cards) or a free spell for you, both seem really handy for only 4 mana.

I also can't stand Assassin's Creed on a visceral level, and feel weird about much of UB (Transformers is hard to fit in most lists without looking ridiculous), but I felt I had to mention them! I'm glad to hear the deck is working for you, it looked like a ton of fun!

I've always loved Reanimator in Legacy, it's crazy to see how much it's changed over the years! We've come a long way from Deep Spawn! It's cool that Animate Dead still makes the cut.

A lot of decks like this sneak in a Children of Korlis to recoop all life already paid to Griselbrand (thus letting you draw that much over again). FWIW I think Children would make Borborygmos Enraged a better card since Children can help you draw your entire deck, potentially letting you win on your first turn (if you're lucky enough).

I think there wouldn't be much opportunity cost to throwing in a single Scrubland (and some Fetches to find it), but that's a huge budget jump, but if you want to play at tournaments I think Children are a really high ceiling include potentially. That said I'd include Children even if you don't have any lands able to cast them, they're a great reanimation target in my experience.

I think this is an efficient and threatening deck; being able to switch to Discard vs opposing combo decks seems pretty sweet. I could see Surgical Extraction in your sideboard, not sure how many would make sense, maybe x2. I'm a lot less sure about this, but maybe you should add x1 Witherbloom Apprentice from your Maybeboard, even x1 with x4 Entomb should be enough to get by.