Thunder

Thunder monsters gain a boost from Umi and Mountain. Some of the stronger ones include Batteryman AA, Super-Electromagnetic Voltech Dragon, The Creator and Zaborg the Thunder Monarch. In the TCG, Thunder-type monsters have almost no specific support (excluding the likes of Electro-Whip), but the OCG has Makiu which is support for Thunders (and Summoned Skull). Thunder Dragon is a commonly used thunder monster, for his deck-thinning abilities and for his fusion counterpart, Twin-Headed Thunder Dragon.

Thunder-type monsters are generally Light.

The strongest Thunder Monster would probably be Hamon, Lord of Striking Thunder.