Direct tumor extension into the stomach, duodenum, small bowel or large bowel History of gastric or small bowel surgery involving any extent of gastric or small bowel resection. Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, gastric bypass, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction. Unable to swallow capsules or tablets or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Participants with any condition that could interfere with the absorption or metabolism of ibrutinib including malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel Unable to swallow capsules, malabsorption syndrome, disease significantly affecting gastrointestinal function, resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Patients unable to swallow tablets or capsules, those with uncontrolled vomiting or diarrhea or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption such as: malabsorption syndrome, resection of the small bowel, or poorly controlled inflammatory bowel disease affecting the small intestine CRITERIA SPECIFIC FOR COHORT #2 (MCL): Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction likely to interfere with the delivery, absorption, or metabolism of lenalidomide Malabsorption syndrome, disease significantly affecting gastrointestinal function, resection of the stomach or small bowel, or ulcerative colitis Unable to swallow capsules or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption such as; malabsorption syndrome, resection of the small bowel, or poorly controlled inflammatory bowel disease affecting the small intestine Is unable to swallow capsules, has a partial or small bowel obstruction, or has a gastrointestinal condition resulting in a malabsorptive syndrome (e.g. small bowel resection with malabsorption) Malabsorption syndrome, ulcerative colitis, inflammatory bowel disease, resection of the stomach or small bowel, or other disease or condition significantly affecting gastrointestinal function Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function; resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Gastrointestinal disease that might inhibit ibrutinib absorption (e.g., malabsorption syndrome, resection of the stomach or a large portion of small bowel, or partial/complete bowel obstruction), or unable to swallow capsules Malabsorption syndrome, disease significantly affecting gastrointestinal function, resection of the stomach, extensive small bowel resection that is likely to affect absorption, symptomatic inflammatory bowel disease, partial or complete bowel obstruction, or gastric restrictions and bariatric surgery, such as gastric bypass. Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction likely to interfere with the delivery, absorption, or metabolism of venetoclax or lenalidomide Direct tumor extension into the stomach, duodenum, small bowel or large bowel Unable to swallow capsules, malabsorption syndrome, prior resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, partial or complete bowel obstruction, or any other disease significantly affecting gastrointestinal function Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease, partial or complete bowel obstruction, or gastric restrictions and bariatric surgery, such as gastric bypass Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Clinically significant ulcerative colitis, inflammatory bowel disease, or partial or complete small bowel obstruction are to be excluded Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction, or any other gastrointestinal condition that could interfere with the absorption and metabolism of ibrutinib Malabsorption syndrome, ulcerative colitis, inflammatory bowel disease, resection of the stomach or small bowel, or other disease or condition significantly affecting gastrointestinal function. Relapsed/refractory MCL: Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Newly diagnosed MCL: Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, ulcerative colitis, inflammatory bowel disease, partial or complete small bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Patients with history of prior bowel resection, malabsorption syndrome, inflammatory bowel disease, prior bowel obstruction (partial or complete), Crohn disease, or any other disease significantly affecting the gastrointestinal tract History of gastric or small bowel surgery involving any extent of gastric or small bowel resection. Unable to swallow capsules, has a partial or small bowel obstruction, or has a gastrointestinal condition resulting in a malabsorptive syndrome (e.g. small bowel resection with malabsorption) Inability to swallow capsules or tablets, or disease significantly affecting gastrointestinal\r\nfunction and/or inhibiting small intestine absorption (malabsorption syndrome, resection\r\nof the small bowel, poorly controlled inflammatory bowel disease, etc.) Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction. Unable to swallow capsules, or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption, such as malabsorption syndrome, resection of portions of small bowel larger than 3 feet, or poorly controlled inflammatory bowel disease affecting the small intestine Unable to swallow capsules, or disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, or symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Malabsorption syndrome, ulcerative colitis, resection of the stomach or small bowel, or other disease significantly affecting gastrointestinal function Current refractory nausea and vomiting, malabsorption syndrome, disease significantly affecting gastrointestinal (GI) function, resection of the stomach, extensive small bowel resection that is likely to affect absorption, symptomatic inflammatory bowel disease, partial or complete bowel obstruction, or gastric restrictions and bariatric surgery, such as gastric bypass. Inability to swallow capsules or presence of malabsorption syndromes, disease significantly affecting gastrointestinal function, history of resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete small obstruction Patients unable to swallow capsules, or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption, such as malabsorption syndrome, resection of the small bowel, or poorly controlled inflammatory bowel disease affecting the small intestine are ineligible Unable to swallow capsules, or disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Malabsorption syndrome, disease significantly affecting gastrointestinal function, resection of the stomach, extensive small bowel resection that is likely to affect absorption, symptomatic inflammatory bowel disease, partial or complete bowel obstruction, or gastric restrictions and bariatric surgery, such as gastric bypass Able to swallow capsules without difficulty and no history of malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or active ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or disease significantly affecting gastrointestinal function such as malabsorption syndrome, resection of the stomach or small bowel, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Current refractory nausea and vomiting, malabsorption syndrome, disease significantly affecting gastrointestinal function, resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Malabsorption, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Unable to swallow capsules or has malabsorption syndrome, disease significantly affecting gastrointestinal function or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease, partial or complete bowel obstruction. Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease, partial or complete bowel obstruction, or gastric restrictions and bariatric surgery, such as gastric bypass Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Inability to swallow capsules or tablets, or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption (malabsorption syndrome, resection of the small bowel, poorly controlled inflammatory bowel disease, etc.) Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction, or any other gastrointestinal condition that could interfere with the absorption and metabolism of ONC201 Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease, partial or complete bowel obstruction Other nonmalignant systemic disease that would preclude the patient from receiving study treatment or would prevent required follow up such as: Active infection or chronic infection requiring chronic suppressive antibiotics; Malabsorption syndrome, ulcerative colitis, inflammatory bowel disease, resection of the stomach or small bowel, or other disease or condition significantly affecting gastrointestinal function; Chronic daily treatment with corticosteroids with a dose of greater than or equal to 10 mg/day methylprednisolone equivalent (excluding inhaled steroids); Seizure disorders requiring medication. Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction, or any other gastrointestinal condition that could interfere with the absorption and metabolism of ibrutinib Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction. Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or gastric bypass, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction. Subjects unable to swallow capsules or with disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption, such as malabsorption syndrome, resection of the stomach or small bowel, partial or complete bowel obstruction, or symptomatic inflammatory bowel disease are not eligible Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction. Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction. Patient must be able to swallow capsules and not have the following conditions:\r\n* Disease significantly affecting gastrointestinal function\r\n* Resection of the stomach or small bowel\r\n* Symptomatic inflammatory bowel disease\r\n* Ulcerative colitis\r\n* Partial or complete bowel obstruction Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction. Malabsorption syndrome, ulcerative colitis, inflammatory bowel disease, resection of the stomach or small bowel, or other disease or condition significantly affecting gastrointestinal function. Unable to swallow capsules, malabsorption syndrome, disease significantly affecting gastrointestinal function, resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction or other condition that precludes enteral route of administration Unable to swallow capsules, or disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, or symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or disease significantly affecting gastrointestinal function or resection of the stomach or small bowel, or symptomatic inflammatory bowel disease or ulcerative colitis or partial or complete bowel obstruction Unable to swallow capsules or disease significantly affecting gastrointestinal function such as malabsorption syndrome, resection of the stomach or small bowel, or complete bowel obstruction Unable to swallow capsules or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption such as; malabsorption syndrome, resection of the small bowel, or poorly controlled inflammatory bowel disease affecting the small intestine Unable to swallow capsules or known malabsorption syndrome, known disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, uncontrolled symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction, at the time of study entry Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease, partial or complete bowel obstruction, or gastric restrictions and bariatric surgery, such as gastric bypass. Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction. Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel or symptomatic ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Direct tumor extension into the stomach, duodenum, small bowel or large bowel Unable to swallow capsules, or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption, such as malabsorption syndrome, resection of the small bowel, or poorly controlled inflammatory bowel disease affecting the small intestine Inability to swallow capsules whole, or disease significantly affecting gastrointestinal function and/or inhibiting small intestine absorption, such as malabsorption syndrome, small bowel resection, or poorly controlled inflammatory bowel disease affecting the small intestine Persistent diarrhea or malabsorption >= National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) grade 1, despite medical management, ulcerative colitis, inflammatory bowel disease, resection of the stomach or small bowel, or other disease or condition significantly affecting gastrointestinal function Unable to swallow capsules, or disease significantly affecting gastrointestinal function or resection of the stomach or small bowel, or symptomatic-inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Presence of active GI disease or other condition (e.g., small bowel or large bowel resection) that will interfere significantly with the absorption of drugs. Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel; Malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, ulcerative colitis, symptomatic inflammatory bowel disease, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Patient is unable to swallow capsules or has a disease or condition significantly affecting gastrointestinal function, such as malabsorption syndrome, resection of the stomach or small bowel, or complete bowel obstruction Patients with intestinal issues, including malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel EXCLUSION CRITERIA (PRIOR TO IBRUTINIB ADMINISTRATION): Unable to swallow capsules or malabsorption syndrome, disease significantly affecting gastrointestinal function, or resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Current refractory nausea and vomiting, malabsorption syndrome, disease significantly affecting gastrointestinal function, resection of the stomach or small bowel, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction Unable to swallow capsules or malabsorption syndrome, symptomatic inflammatory bowel disease or ulcerative colitis, or partial or complete bowel obstruction at time of screening