Sure, it had ways to destroy permanents likes creatures with flying as well artifacts and enchantments, but straight-up creature removal was something it sorely lacked for many years
Legality depends on the tournament format -- Urza, Lord High Artificer can be legal in some formats and banned or restricted in others
Creatures suffer from summoning sickness, which means they cannot attack or use abilities that require tapping unless theyve been under your control since the start of your turn
Korvold, Fae-Cursed King One of the most busted sacrifice commanders in the game, Korvold, Fae-Cursed King tends to exploit Treasure more often than other creatures, but its still lets you sacrifice your Shambling Ghast and similar cards while rewarding you with plenty of card draw for taking the game actions your deck wanted to do anyway
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