Dasam Granth on Mahadev
In Dasam Granth, Mahadev is not considered as Supreme being, as in Hinduism, but a human being who is a Yogi. In Chopai, Mahadeva and Shiva are two separate entities, where Shiva is designated for Nirankar. Dasam Granth attributed Akaal as ਮਹਾਦੇਵ ਹੂੰ ਕੇ ਦੇਵ, ਮਹਾਦੇਵ ਹੂੰ ਕੇ ਦੇਵਨਾਥ.
In Hinduism, Mahadeva is primary diety, also called Shiva by Hindus and considered as Supreme God. Mahadev is usually worshiped in form of Ling.
Bachitar Natak
ਮਹਾਦੇਵ ਅਚੁੱਤ ਕਹਾਯੋ ॥ ਬਿਸਨ ਆਪ ਹੀ ਕੋ ਠਹਿਰਾਯੋ ॥
महादेव अचु्त कहायो ॥ बिसन आप ही को ठहिरायो ॥
Mahadeo (Shiva) was called Achuta (Unborn), Vishnu considered himself the Supreme.
ਬ੍ਰਹਮਾ ਆਪ ਪਾਰਬ੍ਰਹਮ ਬਖਾਨਾ ॥ ਪ੍ਰਭ ਕੋ ਪ੍ਰਭੂ ਨ ਕਿਨਹੂੰ ਜਾਨਾ ॥੮॥
ब्रहमा आप पारब्रहम बखाना ॥ प्रभ को प्रभू न किनहूं जाना ॥८॥
Brahma called himself PaarBrahma, none of above comprehend the Lord.8.
Akal Ustat
ਦੇਵਨ ਕੋ ਦੇਵ ਮਹਾਦੇਵ ਹੂੰ ਕੇ ਦੇਵ ਹੈਂ ਨਿਰੰਜਨ ਅਭੇਵ ਨਾਥ ਅਦ੍ਵੈ ਅਬਿਨਾਸਿ ਹੈਂ ॥੧੦॥੨੬੨॥
देवन को देव महादेव हूं के देव हैं निरंजन अभेव नाथ अद्वै अबिनासि हैं ॥१०॥२६२॥
He is the God of Gods and God of Maha deva, He is Transcendent, Indiscriminate, Non-dual and Immortal Lord. 10.262.
ਦੇਵਨ ਕੇ ਦੇਵ ਮਹਾਦੇਵ ਹੂੰ ਕੇ ਦੇਵਨਾਥ ਭੂਮ ਕੇ ਭੂਜਯਾ ਹੈਂ ਮੁਹਯਾ ਮਹਾ ਬਾਲ ਕੇ ॥ (Bachitar Natak)
Krishna Avtar
Khadag Singh vs. Mahadev,Ganesh and Kartikey
In story of Kharag Singh fighting with Krishna, Mahadev was beaten badly by Kharag Singh including his two sons, Ganesha and Kartikeya.