He is less punchy due to no haste but lifegain is probably a comparable value trade off
The Ur-Dragon - The Favorite Dragon decklist -
The card was an immediate hit in the format, particularly due to Kaalia of the Vast decks that could cheat it into play and get around the fact that it normally has to attack by its lonesome
With excellent stats across the board and an Evasive feature, however, it's no surprise that TCGPlayer puts her value at $208
The main purpose of Mechtitan Core is to get it on the battlefield with a bunch of other Vehicles or artifact creatures and turn it into Voltrona 10/10 flying, hasty, lifelinking, trampler that can kill our opponent in just two attacks
Having access to it every game, at all points of the game, makes your deck incredibly resilient and strong