A 6-mana creature that must survive a turn cycle to have an impact doesnt line up with the current format, especially since this elder dinosaur can whiff
For starters, you can offer up creatures to sacrifice outlets like Altar of Dementia and Phyrexian Tower to enable Reincarnation on demand
Having a way to deal with a problematic permanent when you need to and a creature to threaten life totals with when you dont is phenomenal
Controlling decks often use it to win counterwars to keep from dying to opponent's combos, while combo decks use it to protect their combos and force through their game-winning play

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Since red is the primary color of dragons, youre spoiled for choice