Tortoises do not play in the way a dog or a parrot does, so enrichment for a Hermann's tortoise is about giving expression to its natural behaviors rather than entertaining it with toys. The behaviors worth encouraging are grazing, foraging, digging, climbing, basking, and patrolling territory. An enclosure that invites all of these keeps the animal physically fit and mentally engaged, and prevents the dull, repetitive pacing seen in barren setups.
The single most effective form of enrichment is a varied, naturalistic environment. A larger space with changing terrain, planted edible forage, warm stones, slopes, and hides gives the tortoise constant reasons to move and investigate. Rearranging furnishings periodically introduces novelty and keeps the animal exploring rather than settling into a fixed, sedentary routine.
Food-based enrichment plays to the tortoise's strongest instinct. Because so much of a wild tortoise's day is spent seeking and processing food, spreading forage around the enclosure, hiding greens among furnishings, and making the animal work a little for its meal turns feeding into rich, time-consuming activity. This is far closer to natural behavior than presenting all the food in one dish.
Outdoor access is enrichment in its purest form. Sunlight, weather, varied ground, growing plants, and the freedom to roam a larger pen stimulate behaviors that are difficult to fully recreate indoors. For keepers in suitable climates, secure outdoor time during warm weather does more for a tortoise's wellbeing than any single product could.