Thunder Gold Announces Fully Funded Phase Three Drill Program at Tower Mountain

Thunder Bay, Ontario--(Newsfile Corp. - September 23, 2025) - Thunder Gold Corp. (TSXV: TGOL) (FSE: Z25) (OTCQB: TGOLF) ("Thunder Gold" or the "Company") is pleased to announce the fully funded Phase Three drill program at its 100%-owned, 2,500-hectare, Tower Mountain Gold Property, located 50 kilometres west of Thunder Bay, Ontario.

The recently completed Phase Two drilling as announced on September 8, 2025 confirmed Tower Mountain as a highly consistent and scalable gold system, demonstrating the potential for a much larger discovery. The Phase Three drill program is scheduled to commence October 1^st, 2025.

Key Highlights:

• Phase Three Fully Funded Drill Program to begin October 1, 2025 at Tower Mountain.
• 2,000 metres planned, with ~70% focused on infill drilling along the 1,800-metre western contact of the Tower Mountain Intrusive Complex ("TMIC").
• Strategic program designed to advance a pit-constrained Mineral Resource Estimate for the western TMIC contact.
• Program will target gaps in drill coverage to support geological confidence and future resource classification.
• Phase Two results validated continuity of mineralization and demonstrated strong potential to expand mineralization footprint elsewhere around the TMIC.
• Rising gold prices and the project's infrastructure advantages support rapid advancement toward development.

Wes Hanson, President and CEO, states, "We are strategically focusing the Phase Three drilling to rapidly establish the resource potential of the western TMIC contact. Phase Two drilling not only reinforced Tower Mountain's scale and consistency but also validated our approach by demonstrating mineralization continuity and the opportunity to significantly expand the footprint within the western contact of the TMIC.

Phase Three drilling is designed to build on that success by closing the gaps in our coverage, strengthening geological confidence, and move us decisively towards an initial Mineral Resource Estimate (MRE) for the entire western contact of the TMIC.

With gold prices at multi-year highs and robust infrastructure already in place, we are in a strong position to accelerate resource definition while continuing to explore the broader TMIC perimeter. Our strategy is deliberate: establish a robust, near-surface, open-pittable resource that could serve as the foundation for future mining operations, while preserving the upside of systematic discovery across the 2,500-hectare property. Tower Mountain is uniquely positioned to evolve into a district-scale opportunity, delivering long-term value to shareholders and meaningful benefits to Northwestern Ontario."

Phase Three Drill Program Overview (Reference FIGURE 1.0)

3738-Target

To date, a total of seven (7) holes test the 3738-Target area, which is a 300-metre long by 150-metre wide gap between the Bench and Ellen targets. These holes indicate a weight-averaged grade of 0.93 g/t Au (capped at 9.0 g/t Au) over an average downhole interval length of 77.0 metres.

Significant results include:

The Phase Two drill program suggests the 3738-Target mineralization may offer sub-vertical continuity.

A total of five (5) holes (1,050 metres) are currently planned to test the 3738-Target (Reference Figure 2.0).

Hole TM25-180 shall be deepened 100 metres as the last 16.5 metres returned an average grade of 1.87 g/t Au.

Hole TM25-181 shall be deepened 200 metres to intersect 100 metres vertically below the TM25-180 intercept.

Hole TM25-183 (200 metres) targets the area 100 metres above TM25-180.

Holes TM25-184 and 185 (525 metres) are targeted 100 metres above and below hole TM25-178 which intersected 1.25 g/t Au over 103.5 metres.

A Target

To-date, twelve (12) holes have tested the at-surface mineralization at the A-Target returning a weight-averaged grade of 1.29 g/t Au (capped at 9.0 g/t Au) over an average interval length of 22.7 metres. Significant results include:

As at the 3738-Target, the Phase Two drilling suggests sub-vertical continuity of the mineralization. The Phase Three drill program is designed to test this observation with a fence of holes targeting the interpreted dip 100 metres below the current drill coverage.

Two (2) holes (TM25-186 and 187) are currently proposed to test the down dip continuation of the A-Target (Reference Figure 2.0). Both holes are 100 metres in length and target the area 50 metres below the historical drilling described above.

The remaining 950 metres of the Phase Three drill program shall be held in reserve pending visual observation of the currently planned holes. Additional holes may be added at both the 3738 and A-Targets as warranted.

The Company is also considering drilling the UV-Target during the Phase Three drill program. TM04-09 (1.82 g/t Au (capped at 9.0 g/t Au) over 78.0 metres) and TM04-24 (0.93 g/t Au over 88.5 metres) offer a compelling target that remains open to the northwest along strike. These holes currently define the northwest limit of the UV-Target, but access may not be possible until winter.

FIGURE 1.0 DIAMOND DRILL PLAN - WESTERN CONTACT AREA – TOWER MOUNTAIN PROPERTY

Intervals greater than 0.50 g/t Au shown in red.

To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/5364/267478_1621ad7cc410f9ee_001full.jpg

FIGURE 2.0 PHASE THREE DIAMOND DRILL PLAN – 3738 & A TARGETS

Intervals greater than 0.50 g/t Au shown in red.

To view an enhanced version of this graphic, please visit:
https://images.newsfilecorp.com/files/5364/267478_1621ad7cc410f9ee_002full.jpg

Quality Assurance and Quality Control

Diamond drilling utilizes NQ diameter tooling. The core is received at the on-site logging facility where it is, photographed, logged for geotechnical, physical properties and geological data. Samples are identified, recorded, and cut in half by wet diamond saw. Half the core is sent for assay at an accredited laboratory with the remaining half core stored on site. A standard sample length of 1.5 meters is typically employed, varying only at major lithological contacts. Certified standards and blanks are randomly inserted into the sample stream and constitute approximately 10% of the sample stream. Certified standards and blank performance is monitored with any failures evaluated and investigated to determine if said failure is a result of error during submission. Any unexplained failures are identified and the five samples preceding and following the failure are re-assayed. In addition, standards and blanks are inserted into the re-assayed interval stream to monitor analytical performance. Samples are shipped to the Activation Laboratories Ltd. facility in Thunder Bay, Ontario, where sample preparation and analyses are completed. All samples are analyzed for gold using a 30-gram lead collection fire assay fusion (FA) with an atomic absorption (AAS) finish. All assay results greater than 5.0 g/t Au are re-assayed using a gravimetric analysis. All assays greater than 30.0 g/t Au are re-assayed using screen metallics where a representative 1000-gram sample is split sieved at 149µm. Assays are performed on the entire +149 µm fraction and two splits of the -149 µm fraction. A final assay is calculated based on the weight of each size fraction.

Qualified Person

Technical information in this news release has been reviewed and approved by Wes Hanson, P.Geo., President and CEO of Thunder Gold Corp., who is a Qualified Person under the definitions established by National Instrument 43-101.

About the Tower Mountain Gold Property

The 100%-owned Tower Mountain Gold Property is located adjacent to the Trans-Canada highway, approximately 50-km west of the international port city of Thunder Bay, Ontario. The 2,500-hectare property surrounds the largest, exposed, intrusive complex in the eastern Shebandowan Greenstone Belt where most known gold occurrences have been described as occurring either within, or proximal to, intrusive rocks. Gold at Tower Mountain is localized within extremely altered rocks surrounding the Tower Mountain Intrusive Complex, a multi-phase, long duration intrusive complex that control gold distribution on the Property. Historical drilling has established anomalous gold extending out from the intrusive contact for over 500 metres along a 1,500-metre strike length, to depths of over 500 metres from surface. The remaining 75% of the perimeter surrounding the intrusion shows identical geology, alteration, and geophysical response, offering a compelling exploration opportunity.

About Thunder Gold Corp.

Thunder Gold is advancing the Tower Mountain Project in Thunder Bay, Ontario – an emerging gold system with the scale, consistency, and quality to support a long-life, open-pit operation. Results from our disciplined drill programs have consistently reinforced confidence in the continuity and predictability of the discovery, while highlighting significant potential for expansion across multiple zones of the Tower Mountain Intrusive Complex. With industry-leading drilling costs, existing infrastructure and a skilled local workforce, Tower Mountain represents a rare combination of size, scalability, and cost-effective growth.

At Thunder Gold, our vision is clear: to unlock a discovery that has the potential to become a transformational gold project, delivering long-term value for shareholders while contributing to the future of Canada's mining industry. For more information about the Company, please visit:

www.thundergoldcorp.com

On behalf of the Board of Directors,
Wes Hanson, P.Geo., President and CEO

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The information contained herein contains "forward-looking information" and "forward-looking statements" within the meaning of applicable securities legislation (collectively, "forward-looking statements"). Forward-looking statements relate to information that is based on assumptions of management, forecasts of future results, and estimates of amounts not yet determinable. All statements, other than statements of historical fact, are forward-looking statements and are based on predictions, expectations, beliefs, plans, projections, objectives and assumptions made as of the date of this news release, including without limitation; anticipated results of geophysical drilling programs, geological interpretations and potential mineral recovery. Any statement that involves discussions with respect to predictions, expectations, beliefs, plans, projections, objectives, assumptions, future events or performance (often but not always using phrases such as "expects", or "does not expect", "is expected", "anticipates" or "does not anticipate", "plans", "budget", "scheduled", "forecasts", "estimates", "believes" or "intends" or variations of such words and phrases or stating that certain actions, events or results "may" or "could", "would", "might" or "will" be taken to occur or be achieved) are not statements of historical fact and may be forward-looking statements.

Forward-looking statements are subject to a variety of risks and uncertainties which could cause actual events or results to differ from those reflected in the forward-looking statements, including, without limitation: risks related to failure to obtain adequate financing on a timely basis and on acceptable terms; risks related to the outcome of legal proceedings; political and regulatory risks associated with mining and exploration; risks related to the maintenance of stock exchange listings; risks related to environmental regulation and liability; the potential for delays in exploration or development activities or the completion of feasibility studies; the uncertainty of profitability; risks and uncertainties relating to the interpretation of drill results, the geology, grade and continuity of mineral deposits; risks related to the inherent uncertainty of production and cost estimates and the potential for unexpected costs and expenses; results of prefeasibility and feasibility studies, and the possibility that future exploration, development or mining results will not be consistent with the Company's expectations; risks related to the gold price and other commodity price fluctuations; and other risks and uncertainties related to the Company's prospects, properties and business detailed elsewhere in the Company's disclosure record. Should one or more of these risks and uncertainties materialize, or should underlying assumptions prove incorrect, actual results may vary materially from those described in forward-looking statements. Investors are cautioned against attributing undue certainty or reliance on forward-looking statements. These forward-looking statements are made as of the date hereof and the Company does not assume any obligation to update or revise any forward-looking statements, other than as required by applicable law, to reflect new information, events or circumstances, or changes in management's estimates, projections or opinions. Actual events or results could differ materially from those anticipated in the forward-looking statements or from the Company's expectations or projections.

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