Complex sentence: Unlike most Warhammer 40,000 races, the Tyranids do not have a direct Warhammer Fantasy Battle counterpart, but share a horde mentality with the Skaven army and are widely considered Warhammer 40,000's equivalent.
Split into simpler sentences: Unlike most Warhammer 40,000 races, the Tyranids do not have a direct Warhammer Fantasy Battle counterpart. But share a hoarde mentality with the Skaven army and are widely considered Warhammer 40,000's equivalent.