-Personality- Befitting Tirek's status as a revamp of one of G1's darkest characters, Tirek is extremely power-hungry and brutal. He wants to be the ruler and god of Equestria, and he will stop at nothing to accomplish this goal. However, he does not kill his enemies, preferring to leave them alive, but powerless, the better to oppress them. Tirek is very quick to anger, and his wrath is absolutely terrifying to behold.
Despite this, Tirek is not purely a brute - he can be deceptively intelligent. He is shown to be patient, as he waited for a long time after escaping Tartarus, recovering enough power to become able to launch an assault on ponies. Tirek is also an expert manipulator, who cannot be trusted - he was even able to persuade Discord, himself known as an expert master of puppets, into joining him - only to betray him and consume his power after gaining enough magic to do so. Despite this, he will sometimes keep his word - but only when he feels he's not really losing anything out of the deal, such as when he released Twilight's depowered friends.
Hm? It wasn't defeating. Just had just tooken away his power for my own gain. To think a 'legend' like him would be 'friends' with those...*Shudders* Ponies.