Here are the common fasts practiced by Digambar Jains during the 10-day Dash Lakshan Parva, with their usual meanings and what is allowed to eat/drink in each. Note that exact practices can vary by sangh and personal vow; many people customize with the guidance of their guru or local monk.

• Upvas (fasting day)

- What it is: A day of giving up regular meals; usually light, mindful eating is kept as a discipline. - Food/water: Often one or two small, sattvik meals are allowed depending on capacity; many aim to eat only before sunset. No roots or flesh, and avoid overindulgence. Water is typically allowed, but practitioners may choose to limit intake.

• Ekāsan (one meal a day)

- What it is: Eat only one meal in the day. - Food/water: A single sattvik meal; water may be allowed as needed but no eating after the meal. If one follows stricter maryādā, even this meal might be postponed to before sunset.

• Biāsanā (two meals a day)

- What it is: Eat two meals in the day. - Food/water: Two sattvik meals; water is allowed as needed during the day, within daylight hours.

• Chauvihar Upvas (no food and water after sunset)

- What it is: Fast from after sunset until next day Navkarsi (the day’s first fast-breaking time). - Food/water: No food or water after sunset; may drink water before sunset or break the fast the next day in the allowed window.

• Tivihar Upvas (no food after sunset; water allowed until midnight)

- What it is: Similar to Chauvihar but allows water until midnight. - Food/water: No food after sunset; water permitted until midnight; next day resumes usual eating.

• Duvihār Upvas (no food after sunset; water, milk, medicine allowed)

- What it is: A stricter form where food is withheld after sunset; liquids like water and sometimes milk/medicines may be taken. - Food/water: No solid food after sunset; fluids (often boiled or permitted) may be taken as per local custom.

• Nirjāla Upvas (waterless fast)

- What it is: No water or food for the fast duration. - Food/water: No water and no food; typically only air and endurance are allowed; usually undertaken for shorter periods under strict guidance.

• Athai (8-day fast)

- What it is: A continuing stretch of fasting for eight days. - Food/water: Typically very light meals or minimal nourishment; many drink only boiled water or avoid solid foods for the entire period, depending on capacity.

• Navai (9-day fast)

- What it is: A nine-day fasting period. - Food/water: Similar to Athai, often continuing with minimal or no solid food; boiled water may be used in some practices.

• Masakhshaman (one-month fast)

- What it is: A longer month-long fasting discipline. - Food/water: Usually very restricted; some styles allow boiled water only, others allow small sattvik foods depending on capacity and guidance.

• Varshita/Varshitāpa style fasting (36 hours on alternate days, 13 lunar months)

- What it is: A seasonal, longer-cycle fast; not always observed by all communities, but practiced by some Digambars. - Food/water: Alternating days may involve no food or water for certain intervals; specifics vary by tradition.

Important notes

• The core aim of these fasts is self-purification and restraint, especially around food, water, and sensual pleasures, during the 10 days of Dash Lakshan. The exact level of austerity (lowest, average, extreme) is often described and chosen by each devotee or sangh. ( jainpedia.org)
• Digambar Dash Lakshan is distinct from Shvetambar Paryushan; Digambar practice emphasizes the ten virtues and often stricter fasting patterns for the festival period. Daily practices typically include pratikraman, samayik, swadhyaya, and dana, besides the vow of fasting or lighter diet according to capacity. ( jainknowledge.com, parliamentofreligions.org)

If you want, I can point you to a Digambar-specific guide with day-by-day recommendations for the current year. You can read more here and about the Das Lakshan acts here .

You can read more on the general fasting forms for Jainism here .